Physics Final Exam Review

What is the momentum of a fly if it's traveling 1.50 m/s and has a mass of 0.000283 kg?

0.0004245 kg-m/s

You drop a lead ball on a cement floor from a height of 8 m. When the ball stops bouncing, how much will its temperature have risen? Assume specific heat for lead equal to 128 J/kg·K.

0.613 K

While polishing a 1.5-kg brass statue, you do 860 J of work against sliding friction. Assuming that all of the resulting heat flows into the statue, how much does its temperature rise? Assume specific heat for brass equal to 380 J/kg·K.

1.5 K

When you ride a bicycle, your foot pushes down on a pedal that's 17.3 cm (0.173 m) from the axis of rotation. Your force produces a torque on the crank attached to the pedal. Suppose that you weigh 688 N. If you put all your weight on the pedal while it's directly in front of the crank's axis of rotation, what torque do you exert on the crank?

119.024 N-m

The builders of the pyramids used a long ramp to lift 22000-kg (22.0-ton) blocks. How much work was done in raising one of the blocks to a height of 52.0 m? Use g=9.81m/s2.

12.6 J

Drilling a hole in a piece of wood takes 1200 J of work. How much does the total internal energy of the wood and drill increase as a result of this process?

1200 J

You stir 2 kg of water until its temperature rises by 1.5 ˚C. How much work did you do on the water? Assume water's specific heat equal to 4190 J/kg·K.

12570 J

If a burning log is a black object with a surface area of 0.20 m2 and a temperature of 800 ˚C, how much power does it emit as thermal radiation?

15031.8 W

What is the rest energy of 2.00 kg of uranium?1

18 x 10^16 J

About how fast can a small (1-cm long) fish swim before experiencing turbulent flow around its body? Assume critical Reynolds number equal to 2300.

23 cm/s

If your car has a mass of 732 kg, how much force is required to accelerate it forward at 3.68 m/s2?

2693.76 N

If you submerge an 8.00-kg log in water and it displaces 11.0 kg of water, what will the net force on the log be the moment you let go of the log? Use g=9.81 m/s2.

29.43 N

If you and a friend 11.0 m away each have masses of 78.0 kg, how much gravitational force are you exerting on your friend?

3.353742148760 x 10^-9 N

An ideally efficient steamboat engine operates on 440 K steam in 260 K weather. How much work can it obtain when 800 J of heat leaves the steam?

327 J

Your car is broken, so you're pushing it. If your car has a mass of 834 kg, how much momentum does it have when it's moving forward at 4.55 m/s (16.4 km/h)?

3794.7 kg-m/s

How much force must a locomotive exert on a 10920-kg boxcar to make it accelerate forward at 0.410 m/s2?

4.477 kN

When someone throws a football, what should the launch angle be (ignoring air resistance) so that it travels a maximum distance?

45 Degrees

How much force is the air exerting on the front surface of the book with dimensions 19.0 x 28.0 cm. Assume atmospheric pressure equal to 100,000. Pa.

5320 N

When your car is moving at 3.74 m/s and car has a mass of 896 kg, how much translational kinetic energy does it have?

6266.45 J

How much does a 72.0 kg person weigh on earth? Use g=9.81 m/s2.

706.32 N

A sprinter can reach a speed of 9.70 m/s in 1.19 s. If the sprinter's acceleration is constant during that time, what is the sprinter's acceleration?

8.15 m/s2

Let your car have a mass of 861 kg. Your car is moving at a speed of 3.30 m/s when it strikes a parked car and stops in 0.29 s. What force did the parked car exert on it to stop it that quickly?

9.797 k-N

As a 70-kg person stands at the seashore gazing at the tides (which are caused by the Moon), how large is the gravitational force on that person due to the Moon? The mass of the Moon is 7.35 × 1022 kg, the distance to the Moon is 3.82 × 108 m, and G = 6.67 × 10-11 N · m2/kg2 A 0.0024 N B. 0.24 N C. 0.024 N D. 0.00024 N

A 0.0024 N

In how many of the following situations does the car have a westward acceleration? -- The car travels westward at constant speed -- The car travels eastward and speeds up. -- The car travels westward and slows down. -- The car travels eastward and slows down -- The car starts from rest and moves toward the east A. 1 B. 3 C. 2 D. All of the given situations

A. 1

You push on a box with a horizontal force of 20 N and the box moves a distance of 8 m. The amount of work you have done on the box is A. 160 J B. 20J C. 0 D. 320 J

A. 160 J

Suppose you are changing a car tire and loosening a lug nut. You weigh 800N and stand on the end of a 2 m long wrench. How much torque do you exert on the lug nut? A. 1600 N-m B. 1600 J C. 2 N-m D. 800 N-m

A. 1600 N-m

You work in a clock shop and are dealing with an irate customer whose clock you are restoring. They notice that the period of the pendulum in their clock is 2 s and they want to double it. So they insist that you replace the pendulum with one of the same dimensions but just heavier. So you do this. When you get the clock repaired, you and the customer check out the clock's period and find it to be A. 2 s B. 4 s C. 8 s D. 16 s

A. 2 s

When the saw slices wood, the wood exerts a 107-N force on the blade, 0.215 m from the blade's axis of rotation. If that force is at right angles to the lever arm, how much torque does the wood exert on the blade? Does this torque make the blade turn faster or slower?

A. 23.005 N-m B. Slower

The onset of turbulent flow happens for a Reynolds number of about... A. 2300 B. 5000 C. 0 D. Infinity

A. 2300

An ideally efficient heater adds 1100 J of heat to a warm room. How much work does it perform if it removes 1400 J of energy from the outdoors? A. 300 J B. 2800 J C. 400 J D. 0 - this can't be done.

A. 300 J

The following pairs of temperatures represent the temperatures of hot and cold reservoirs for heat engines. Which heat engine has the highest possible efficiency? A. 300°C, 30°C B. 250°C, 30°C C. 200°C, 20°C D. 100°C, 10°C E. 90°C, 0°C

A. 300°C, 30°C

A popular playground toy is a flexible seat that has automobile springs attached to it for a little bounce. When a 200 N child sits on the toy, it compresses 5 mm downward. What is the ride's spring constant? A. 40000 N/m B. 1000 N/m C. 5 mm D. 1000 N

A. 40000 N/m

The coefficient of restitution for a particular ball is 0.45. If he ball hits a surface traveling at 100 m/s its rebound speed will be A. 45 m/s B. 90 m/s C. 100 m/s D. 45 m/s2

A. 45 m/s

The maximum height above the ground for a the gymnast jumping straight upward with an initial speed of 10 m/s is A. 5 m B. 10 m C. 2 m D. 15 m

A. 5 m

You walk in a given direction for 20 m during the first 5 seconds of a trip and then 15 m during the next 2 seconds. Your average speed is equal to A. 5 m/s B. -5 m/s C. 8 m/s D. 2 m/s

A. 5 m/s

A car starts from rest and accelerates at 4 m/s2. How much time will it take the car to reach a speed of 20 m/s? A. 5 s B. 10 s C. 4 s D. 8 s

A. 5 s

In Europe an electric razor completes 50 vibrations in 1 second. The frequency of these vibrations is A. 50 Hz with a period of 1/50 second B. 1/50 Hz with a period of 50 seconds C. 50 Hz with a period of 50 seconds D. 1/50 Hz with a period of 1/50 second

A. 50 Hz with a period of 1/50 second

A heat engine receives 7000 J of heat and loses 3000 J in each cycle. What is the efficiency of this engine? A. 57% B. 70% C. 30% D. 43%

A. 57%

What is the gravitational force that two 100 kg persons exert on each other when standing 1m apart? A. 6.672x10-7N B. 1 N C. 6.672x10-11N D. 10,000 N

A. 6.672x10-7N

An object may have potential energy because of its A. Acceleration B. Speed C. Height D. Momentum E. None of the above

A. Acceleration

25) The Bernoulli effect is responsible for the lift force on an airplane wing. Wings must therefore be designed so as to insure that A. Air molecules move more rapidly past the upper surface of the wing than past the lower surface B. Air molecules will be deflected downward when they hit the wing C. Air molecules move more rapidly past the lower surface of the wing than past the upper surface D. Air molecules will be deflected upward when they hit the wing.

A. Air molecules move more rapidly past the upper surface of the wing than past the lower surface

The vibrations along a longitudinal wave move in a direction A. Along the wave B. Perpendicular to the wave C. Both of these D. None of these.

A. Along the wave

Consider a flat steel plate with a hole through its center as shown in the figure. When the temperature of the plate is increased, the hole will A. Always expand with the plate B. Expand only if it takes up more than half the plate's surface area C. Remain the same size as the plate expands around it D. Contract if it takes up less than half the plate's surface area E. Always contract as the plate expands into it.

A. Always expand with the plate

Why is your velocity continuously changing as you ride on a carousel? A. Because your direction of motion is continuously changing. B. Because your speed is continuously increasing and decreasing as your direction changes. C. This is not true, because your speed is not changing D. This is only true if you are on a carousel animal which is constantly moving up and down.

A. Because your direction of motion is continuously changing.

Which of the following is an example in which you are traveling at constant speed but not at constant velocity? A. Driving around in a circle at exactly 100 km/hr B. Driving backward at exactly 50 km/hr C. Rolling freely down a hill in a cart, traveling in a straight line D. Jumping up and down, with a period of exactly 60 hops per minute E. None of the above

A. Driving around in a circle at exactly 100 km/hr

Why are good thermal conductors generally good electric conductors also? A. Electron motion is responsible for determining both properties. B. Heat and electricity are the same things. C. The molecules in both don't move around very much. D. The answer depends on the specific metal.

A. Electron motion is responsible for determining both properties.

Which of the following quantities is not conserved? A. Entropy B. Momentum C. Angular momentum D. Energy

A. Entropy

If you are backing up but slowing down, your acceleration is directed A. Forwards B. To the left C. Backwards D. Nowhere

A. Forwards

A hydraulic device has two pistons, one with a small cross-section area and another piston with a larger cross-section area. If a given force is applied to the small piston, the output force on the larger-area piston will be A. Greater B. Less C. The same D. All of the above E. None of the above

A. Greater

You are taking a shower in your dormitory when someone flushes a toilet nearby. The pressure in the cold water line drops and you find yourself showering in what feels like molten lava. This loss of cold water pressure occurs when the toilet lets cold water flow through the pipes delivering it to the bathroom and the water's speed in those pipes increases. Assuming all the piping to be about on the same level, the cold water's faster motion in the delivery pipes reduces its pressure in the shower head because faster moving water.... A. Has less pressure than slower moving water B. Has less kinetic energy than slower moving water C. Has less gravitational potential energy than slower moving water D. Losses more energy to viscous drag as it flows through the delivery

A. Has less pressure than slower moving water

Why does an ice cube feel cold? A. Heat from your hand enters the cube by conduction. B. Cold from the cube enters your hand by conduction. C. Heat from your hand enters the cube by convection. D. Cold from the cube enters your hand by convection.

A. Heat from your hand enters the cube by conduction.

The Law of Conservation of Energy says... A. Heat in equals change in internal energy plus work done. B. Heat in plus change in internal energy equals work done. C Heat in plus work done equals change in internal energy. D. Heat in equals work done.

A. Heat in equals change in internal energy plus work done.

When you pour honey into a bowl, it flows smoothly. If you did the same with water, it would splash. These different behaviors occur because honey's... A. High viscosity keeps it flowing smoothly while water's low viscosity allows inertia to break its flow into many separate pieces B. Momentum keeps it moving in a straight line while water's low momentum allows it to turn abruptly in many different directions C. Density keeps it flowing smoothly while water's low density allows it to float upward and splash about D. Mass keeps it flowing smoothly while water's low mass allows it to acquire lots of angular momentum.

A. High viscosity keeps it flowing smoothly while water's low viscosity allows inertia to break its flow into many separate pieces

It is a hot summer day and your friend's apartment has no air conditioning. However, a brand new refrigerator lies unopened in the center of the living room. Being a creative person, your friend closes all the doors and windows of the apartment, unpacks the refrigerator, plugs it in, and turns it on. Your friend then opens the refrigerator door and uses a small fan to circulate the air past the refrigerator and throughout the room. After the refrigerator has operated for a few minutes, the average temperature in the room is... A. Higher than it was before. B. The same as it was before and the temperature is uniform throughout the room. C. Lower than it was before. D. The same as it was before, but some regions are hotter and others are colder.

A. Higher than it was before.

The change in momentum of an object is equal to the A. Impulse that acts on it B. Change in its velocity C. Object's mass times the force acting on it D. Force acting on it E. All of the above

A. Impulse that acts on it

A steady force pushes in the piston of a well-insulated cylinder. In this process, the temperature of the gas... A. Increases B. Stays the same C. Decreases D. There's not enough E. information to tell

A. Increases

The "strokes", or "cycles" in a four - stroke engine are... A. Induction, compression, power, exhaust B. Ignition, compression, power, exhaust C. Ignition, induction, power, exhaust D. Vacuum, compression, ignition, exhaust

A. Induction, compression, power, exhaust

A Diesel engine is more efficient than a gasoline engine because A. It has a higher temperature and can therefore convert more heat into work B. It has a higher temperature and can therefore convert less heat into work C. It has a lower temperature and can therefore convert more heat into work D. It has a lower temperature and can therefore convert less heat into work.

A. It has a higher temperature and can therefore convert more heat into work

A moving object has inertia, which means... A. It will move at constant velocity unless there are outside forces acting on it. B. It will always keep moving. C. It will tend to slow down and stop. D. Gravity will affect it.

A. It will move at constant velocity unless there are outside forces acting on it.

A projectile is thrown directly upward and caught again. At the top of its path A. Its vertical velocity is zero B. It stops accelerating C. Its horizontal velocity changes D. Its acceleration changes

A. Its vertical velocity is zero

A curve ball in baseball curves because of A. Lift forces B. Drag forces C. Gravitational forces D. Buoyant forces.

A. Lift forces

The density of freshwater is 1 g/cm 3 and the density of seawater is 1.03 g/cm 3. A ship will float A. Lower in freshwater than in sea water B. Higher in freshwater than in sea water C. Could be higher or lower in any water depending on the shape of the ship D. At the same level in freshwater and seawater

A. Lower in freshwater than in sea water

What quantities does angular momentum depend upon? A. Mass and velocity B. Rotational mass and angular velocity C. Force, velocity, and radius D. Momentum and angular velocity E. Force and radius

A. Mass and velocity

In countless movie and television scenes, the hero punches a brawny villain who doesn't even flinch at the impact. Why is the immovable villain a Hollywood fantasy? A. Momentum must be conserved. B. The impulse of the hero's fist is greater than the impulse of the villain's jaw. C. Energy must be conserved. D. Angular momentum must be conserved.

A. Momentum must be conserved.

A pedestrian bridge crosses a street. This bridge is entirely supported by columns from below. A gap at each end of the bridge separates the bridge's surface from the sidewalks leading to the bridge. The width of each gap changes with time. This width is smallest A. On hot days B. At noon C. At midnight D. On cold day

A. On hot days

Melting is a ______ that requires energy ________ for the melting system A. Phase transition; input B. Chemical change; input C. Phase transition; release D. Chemical change; release

A. Phase transition; input

Melting is a _______ ______ that requires energy ________ for the melting system. A. Phase transition; input B. Chemical change; input C. Chase transition; release D. Chemical change; release

A. Phase transition; input

Freezing is a ____________ that requires energy ________ for the melting system A. Phase transition; release B. Phase transition; input C. Chemical change; release D. Chemical change; input

A. Phase transition; release

The amount of water flowing through a hose is... A. Proportional to the pressure difference between the ends of the hose B. Proportional to the square of the diameter of the hose C. Proportional to the length of the hose D. Proportional to the viscosity of the water

A. Proportional to the pressure difference between the ends of the hose.

Suppose your car's speed doubles. By what factor will its kinetic energy change? A. Quadruple B. Double C. Remain constant D. Can't tell

A. Quadruple

It is possible for two objects of equal mass to have rotational masses because A. Rotational mass depends on total mass and mass distribution in radial distance B. The objects may be made out of different materials C. Rotational mass is always half the total mass D. An object not rotating has no rotational mass.

A. Rotational mass depends on total mass and mass distribution in radial distance

When stringing telephone lines between poles in the summer, it is advisable to allow the lines to A. Sag B. Be taut C. Be close to the ground D. Allow ample space for birds

A. Sag

Suppose you are driving north and suddenly hit your brakes to avoid a dog in the road. As you come to a stop your acceleration is directed A. South B. Nowhere because acceleration is a scalar C. North D. Downwards

A. South

Fluids have viscosity because... A. The atoms and molecules within the fluid interact with each other, producing internal frictional forces B. The atoms and molecules within the fluid are heavy and hard to push C. Molecules in fluids are long and get tangled D. They are always in contact with some boundary.

A. The atoms and molecules within the fluid interact with each other, producing internal frictional forces

The heads of different golf clubs are angled to give the golf ball different initial velocities. The golf ball's speed remains almost constant, but the angle changes with the different clubs. Neglecting any air effects, how does changing the initial angle of the ball affect the distance the ball travels? A. The closer the angle is to 45°, the further the ball goes. B. The shallower the angle, the further the ball goes. C. The distance the ball goes depends only on its initial speed, not the angle. D. The steeper the angle, the further the ball goes.

A. The closer the angle is to 45°, the further the ball goes.

When relative humidity is less than 100%, A. The leaving rate of water molecules exceeds the landing rate. B. The landing rate of water molecules equals the leaving rate. C. The landing rate of water molecules is less than 100%. D. The landing rate of water molecules exceeds the leaving rate.

A. The leaving rate of water molecules exceeds the landing rate.

A high-flying airplane must compress the cold, rarefied outside air before delivering it to the cabin. Why must this air be air-conditioned after the compression? A. The outside air becomes hot during the compression. B. Air conditioning removes excess moisture from the outside air. C. The outside air would not need to be air conditioned if it were not so thin. D. Ths is reverse air-conditioning and raises the temperature of the cold outside air to cabin temperature.

A. The outside air becomes hot during the compression.

As water flows through a bend in a hose, at the inside of the bend... A. The pressure is lower and the speed is higher. B. The pressure is higher and the speed is lower. C. The pressure is higher and the speed is higher. D. The pressure is lower and the speed is lower.

A. The pressure is lower and the speed is higher.

Power is A. The rate at which energy is used, stored, created, dissipated, etc. B. The amount of energy used to do a particular job. C. The amount of energy used multiplied by time. D. The amount of heat generated when a job is done.

A. The rate at which energy is used, stored, created, dissipated, etc.

You are hired as an engineer at a thermometer factory. Suppose you built a water thermometer by replacing the mercury in a mercury thermometer with water. You want to measure temperatures above freezing with it. How would it behave as the temperature drops from 5oC to 1oC? A. The reading will decrease and then begin increasing B. The reading will steadily decrease C. The reading will steadily increase D. The reading will increase and then begin decreasing.

A. The reading will decrease and then begin increasing

When you put a loaf of bread in a plastic bag, there is still air around the bread. Why doesn't the bread dry out as quickly in the bag as it does when there's no bag around it? A. The relative humidity of the air in the bag reaches 100%. B. The water evaporates into the air. C. The water sublimes into the air. D. The bag seals in the moisture.

A. The relative humidity of the air in the bag reaches 100%.

On a bitter cold day, the snow is light and powdery. This snow doesn't begin melting immediately when you bring it into a warm room. Why? A. The snow's temperature needs to rise to 0 °C before it can start melting. B. The snow needs to come up to room temperature before it can start melting. C. The snow needs some time before it can start melting. D. The warmth of the room takes a while to penetrate the snow.

A. The snow's temperature needs to rise to 0 °C before it can start melting.

Suppose you push horizontally on the wall of a building. For you to do work on the wall, which of the following need to happen? A. The wall moves away from you B. The wall lifts up C. The wall moves sideways D. Band C

A. The wall moves away from you

Suppose that we are able to send astronauts to Mars and they engage in a game of golf on the red planet's surface. Given that the atmosphere on Mars is considerably less dense than our own, how will the path of the ball be affected? A. There is less drag and gravity, so the ball will go further than if there were air B. There is less lift, so the ball doesn't go as far than if there were air C. Less air means lower gravity, so it will go further than if there were air D. There is no significant effect.

A. There is less drag and gravity, so the ball will go further than if there were air

When an airplane starts its propellers, they spin slowly at first and gradually pick up speed. Why does it take so long for them to reach their full rotational speed? A. They have a large rotational mass B. Air resistance slows it down C. They have a large mass D. Friction slows it down

A. They have a large rotational mass

Lever arm: A. Times perpendicular force gives torque. B. Is proportional to torque. C. Is the distance from the center of mass to where the force is applied. D. s the distance from the force to where the torque is applied.

A. Times perpendicular force gives torque.

When you pour honey into a bowl, it flows smoothly. If you did the same with water, it would splash. These different behaviors occur because honey's high... A. Viscosity keeps it flowing smoothly while water's low viscosity allows inertia to break its flow into many separate pieces B. Density keeps it flowing smoothly while water's low density allows it to float upward and splash about C. Momentum keeps it moving in a straight line while water's low momentum allows it to turn abruptly in many different directions D. Mass keeps it flowing smoothly while water's low mass allows it to acquire lots of angular momentum

A. Viscosity keeps it flowing smoothly while water's low viscosity allows inertia to break its flow into many separate pieces

You open the refrigerator in your room and put in a case of room-temperature root beer. After an hour, the root beer is ice cold. If your room air did not exchange any heat with the outdoor air during that time, the room air will be... A. Warmer because the refrigerator will have pumped heat out of the root beer and into the room air. B. Warmer because some of the heat from the root beer inevitably leaks out into the room as the result of imperfect insulation. C. Colder because as the refrigerator struggles to cool the root beer, some of the cold it produces inevitably leaks out into the room as the result of imperfect insulation. D. Colder because the refrigerator reverses natural heating, so that things get colder rather than hotter.

A. Warmer because the refrigerator will have pumped heat out of the root beer and into the room air.

How does Newton's Third Law explain why hammerheads are made of hard metal? A. When the head hits the nail, the nail hits the head. B. The head must be heavy to drive the nail. C. The head must be hard to drive the nail. D. The head must be harder than the nail.

A. When the head hits the nail, the nail hits the head.

A metro train is traveling at constant velocity. What are the net forces on (a) the first car, (b) the middle car, and (c) the last car? A. (A.) Backward; (B) Zero; (C) Forward B. (A) Zero; (B) Zero; (C) Zero C. (A) Forward; (B) Forward; (C) Forward D. (A) Forward; (B) Zero; (C) Backward

B. (A) Zero; (B) Zero; (C) Zero

A car was running with velocity 90 m/s. When driver saw a baby on the road, he applied brake and the car stopped after 3 seconds. What is the average acceleration of the car? A. 30 m/s B. -30 m/s 2 C. -30 m/s D. 30 m/s

B. -30 m/s 2

Consider a 100 kg Father and his 20 kg girl. They decide to enjoy balancing on a seesaw, which is a uniform board 4 m long and pivoted exactly at its center. If girl sits at the seesaw's end (2m from the center), how far from the center on the other side should the father sit? A. 1.5 m B. 0.4 m C. 0.5 m D. Farther out than the board will allow.

B. 0.4 m

Atmospheric pressure is about 100000 Pa. At what depth in water does this pressure double? A. 1 m B. 10 m C. 100 m D. 1000 m

B. 10 m

A 500-N weight sits on the small piston of a hydraulic machine. The small piston has an area of 2.0 cm2. If the large piston has an area of 40 cm2, how much weight can the large piston support? Assume the pistons each have negligible weight A. 40000 N B. 10000 N C. 500 N D. 25 N

B. 10000 N

An ideally efficient heater adds 1100 J of heat to a warm room. How much work does it perform if it removes 1400 J of energy from the outdoors? A. 2800 J B. 300 J C. 400 J

B. 300 J

At a speed of 12 m/sec, how far can you travel in one minute? A. 12 m B. 720 m C. 60 m D. 72 m

B. 720 m

When a sample of 0ºC water is heated, it first... A. Expands then contracts B. Contracts then expands C. Remains unchanged D. Continuously expandsE. not enough information

B. Contracts then expands

For momentum to be conserved in a system it must A. Experience no dissipative forces like drag. B. Experience no net external force. C. Be weightless D. Not be connected to a motor.

B. Experience no net external force.

Pressure is A. Area divided by force. B. Force divided by area. C. Force times area. D. A type of force.

B. Force divided by area.

The neighborhood children are playing and one has lost a pocketful of change. As a result they all decide to do a close inspection of the sidewalk. They notice that there are gaps in between the sidewalk filled with a felt - like material. These gaps will prevent A. High stress due to electron "collisions" B. High stress due to thermal expansion C. High stress due to brittleness D. High stress due to the weight of the sidewalk

B. High stress due to thermal expansion

Why can't an acrobat stop himself from spinning while he is in midair? A. Actually, he can. All he has to do is straighten out his body. B. His angular momentum is conserved. C. His momentum is conserved. D. His energy is conserved.

B. His angular momentum is conserved.

The "strokes", or "cycles" in a four - stroke engine are A. Ignition, induction, power, exhaust B. Induction, compression, power, exhaust C. Ignition, compression, power, exhaust D. Vacuum, compression, ignition, exhaust

B. Induction, compression, power, exhaust

Noise-canceling devices such as jackhammer earphones make use of sound A. Destruction B. Interference C. Resonance D. Amplification.

B. Interference

On a cold day your feet feel warmer on a rug than on a tile floor because a rug A. Is usually warmer than tile B. Is a poorer conductor of heat C. For the same mass has more internal energy than tile D. All of the above E. None of the above

B. Is a poorer conductor of heat

As you come to a stop in your car, its momentum A. Is converted to heat energy B. Is changed to zero because of external forces on the car. C. Is dissipated in the form of sound energy D. Remains constant

B. Is changed to zero because of external forces on the car.

Why is "molasses in January" slower than "molasses in July," at least in the northern hemisphere? A. Its Reynolds number decreases at lower temperatures. B. Its viscosity is higher at lower temperatures. C. Its viscosity is lower at lower temperatures. D. Its Reynolds number increases at lower temperatures

B. Its viscosity is higher at lower temperatures.

The airflow around a slow-moving ball is ____ while the airflow around a fast-moving ball is ____. A. Laminar; dependent on pressure gradients B. Laminar; turbulent C. Laminar; dependent on boundary layers D. Lurbulent; laminar

B. Laminar; turbulent

Two liquids, A and B, have equal masses and equal initial temperatures. Each is heated for the same length of time over identical burners. Afterward, liquid A is hotter than liquid B. Which has the larger specific heat? A. Liquid A B. Liquid B C. There's not enough information to tell

B. Liquid B

Mars has a larger orbital radius than the earth. Compare the solar years on those two planets. A. Mars' orbital year is shorter than the earth's. B. Mars' orbital year is longer than the earth's. C. Mars' orbital year is the same length as the earth's. D. There is no specific relationship between the length of Mars' and earth's orbital years.

B. Mars' orbital year is longer than the earth's.

The vibrations along a transverse wave move in a direction A. Along the wave B. Perpendicular to the wave C. Both of these D. None of these.

B. Perpendicular to the wave

The ideal gas law says A. Pressure is proportional to mass density. B. Pressure is proportional to absolute temperature. C. Particle density and pressure are inversely proportional. D. Particle density is proportional to absolute temperature.

B. Pressure is proportional to absolute temperature.

Heat flow is A. Inversely proportional to temperature difference. B. Proportional to surface area. C. Inversely proportional to thermal conductivity. D. Proportional to separation distance.

B. Proportional to surface area.

People fighting forest fires carry emergency tents that have shiny aluminum outer surfaces. If there is trouble, a fire fighter can lie under the tent to block the heat from burning trees overhead. The tent helps because A. Both conduction and radiation carry heat downward toward the fire fighter and the aluminum tent blocks most of that heat B. Radiation carries heat downward toward the fire fighter and the aluminum tent reflects most of that radiation C. Convection carries heat downward toward the fire fighter and the aluminum tent blocks most of the heat carried by convection D. Conduction car

B. Radiation carries heat downward toward the fire fighter and the aluminum tent reflects most of that radiation

When an object is set vibrating by a wave having a frequency that matches the natural frequency of the object, what occurs is A. Forced vibration B. Resonance C. Refraction D. Amplitude enhancement.

B. Resonance

In the constellation Orion, you can easily observe the difference between the reddish looking star Betelgeuse and the bluish looking star Rigel. Which of the two has the hotter surface temperature? A. Betelgeuse B. Rigel C. They have the same surface temperature, since they are in the same constellation D. There is no way to tell since we do not know the exact distance to those stars.

B. Rigel

It is possible for two objects of equal mass to have different rotational masses because A. The objects may be made out of different materials. B. Rotational mass depends on total mass and mass distribution. C. An object not rotating has no rotational mass. D. Rotational mass is always half the total mass.

B. Rotational mass depends on total mass and mass distribution.

Suppose you are riding a bicycle. If you want to waste as little energy as possible while the bike is in motion, what type of friction should exist between the bike and the road? A. Can't tell B. Static C. None D. Sliding

B. Static

What type of friction causes bearings to not waste much energy? A. Neither B. Static C. Sliding D. Both

B. Static

The outdoor portion of a central air-conditioning unit has a fan that blows air across the condenser coils. If this fan breaks, why won't the air conditioner cool the house properly? A. The motor of the compressor requires moving air to run. B. The air blown by the fan carries heat away from the condensor coils. C. The air absorbs the entropy removed from the air in the room. D. The air blown by the fan removes heat directly from the room.

B. The air blown by the fan carries heat away from the condensor coils.

If you seal a soft plastic bottle or juice container while hiking high in the mountains and then return to the valley, the container will be dented inward. What causes this compression? A. The mountain air inside is colder and so it is less dense. B. The air inside the container is at a lower pressure than the air outside. C. The air inside the container takes up less volume once the container dents inward. D. The air inside the container is less dense.

B. The air inside the container is at a lower pressure than the air outside.

Heat capacity is A. Specific heat per mass. B. The amount of heat required to raise the temperature of an object by one unit. C. Also called specific heat. D. The amount of heat required to raise the temperature of a specific mass by one unit.

B. The amount of heat required to raise the temperature of an object by one unit.

When you begin to walk forward, the force that allows you to accelerate is A. The friction force of the ground exerted on your feet. B. The friction force of your feet exerted on the ground. C. The weight of your feet on exerted on the ground. D. The ground pushing up on your feet.

B. The friction force of your feet exerted on the ground.

When cooking a potato in a conventional oven it is useful to stick a nail in it, which makes it cook faster. This is because A. The nail is a good radiator of heat B. The nail is a good conductor of heat C. The nail gets much hotter than anything in the oven D. The nail promotes convection in the potato

B. The nail is a good conductor of heat

If you squeeze a closed bottle filled with water, A. The pressure increases where you are squeezing and decreases at other points. B. The pressure increases by the same amount everywhere in the bottle. C. The pressure increases the most where you are squeezing. D. The pressure does not change.

B. The pressure increases by the same amount everywhere in the bottle.

Suppose you have an aquarium and you notice that you have a solid plastic decoration and a rock of about the same volume but twice as dense, and both are totally submerged in the water. The buoyant force on the plastic object is about ___________ as that on the rock A. Twice as big B. The same C. Half as big D. One quarter as big

B. The same

Suppose you have an aquarium and you notice that you have a solid plastic decoration and a rock of about the same volume but twice as dense, and both are totally submerged in the water. The buoyant force on the plastic object is about ___________as that on the rock. A. Twice as big. B. The same. C. Half as big. D. One quarter as big.

B. The same.

As the moon orbits the earth, which way is the moon accelerating? A. The moon is not accelerating. B. Toward the earth. D. Away from the earth. C. Along its direction of motion.

B. Toward the earth.

The reason fast-moving water makes noise is... A. Chaos B. Turbulence C. Laminar flow D. Vortices

B. Turbulence

Your dryer is broken, so you have to hang your wet clothes from the washing machine outside to dry. Under which conditions would your clothes dry fastest? A. When it is 50°F with 50% relative humidity B. When it is 75°F with 50% relative humidity C. They will dry at the same rate at any temperature with 50% relative humidity D. The clothes will not dry with 50% relative humidity

B. When it is 75°F with 50% relative humidity

A harmonic oscillator is an oscillator A. Which makes musical - like sound when it moves B. With a restoring force proportional to its displacement from equilibrium C. With a restoring force proportional to its speed D. Which has constant kinetic energy when in motion

B. With a restoring force proportional to its displacement from equilibrium

You and your family are on a trip to the local museum and you notice that in the aquarium there are four fish: fish 1 is floating, fish 2 is stationary 2m below the water's surface, fish 3 is stationary 4 m below the water's surface and fish 5 is on the sand at bottom of the tank. (Note: things don't look good for fish 1 and fish 4 but that's beside the3 point here) Your Mom says that she'll buy you lunch if you rank the densities of the fish in order of increasing density, including the density of water in your ranking. Please select your ranking below A. 4 < 2 = 3 B. 1 = 4 < 2 = 3 C. 1 < 2 = 3 = water < 4 D. 4 < 2 = 3 = water < 1

C. 1 < 2 = 3 = water < 4

A plastic block of dimensions 2.00 cm × 3.00 cm × 4.00 cm has a mass of 30.0 g. What is its density? A. 1.20 g/cm3 B. 0.80 g/cm3 C. 1.25 g/cm3 D. 1.60 g/cm3

C. 1.25 g/cm3

What is the weight of water displaced by a 100-ton floating ship? A. More than 100 tons B. Less than 100 tons C. 100 tons D. 100 cubic meters E. Depends on the density of water

C. 100 tons

If you double the absolute temperature of a star, its power output increases by a factor of A. 4 B. 2 C. 16 D. 8

C. 16

A scale from which a rock is suspended reads 5 N when the rock is out of water and 3 N when the rock is submerged. Buoyant force on the rock is A. 3 N B. 4 N C. 2 N D. 5 N

C. 2 N

Suppose you do 1000 J of work on a 5 kg object, and all the work went into lifting it above the ground. How high above the ground will the object be when all the work has been done? A. 100 m B. 5 m C. 20 m D. 1 m

C. 20 m

You operate a 120 W light bulb for 5 minutes. How much energy did you use? A. 120 J B. 3600 J C. 36,000 J D. 36,000 KW - h

C. 36,000 J

If you have a mass of 80 kg and are on a planet where the acceleration of gravity is 5 m/s2, your weight on the planet is A. 80 N B. 4000 N C. 400 N D.16 N

C. 400 N

What is the frequency of a vibration with period 0.02 second? A. 0.02 Hertz B. 0.02 second C. 50 Hertz D. 50 seconds

C. 50 Hertz

To cause a 25 kg object to experience an acceleration of 2 m/s2 the net force that needs to be applied to the object is A. 10 N B. 100 N C. 50 N D. 5 N

C. 50 N

The fundamental frequency of a violin string is 440 hertz. The frequency of its second harmonic is A. 220 Hz B. 440 Hz C. 880 Hz D. None of these.

C. 880 Hz

Which system is in a state of stable equilibrium? A. A marble rolling down an inclined surface. B. A Marble on top of a spherical bowl. C. A marble in the bottom of a spherical bowl. D. A marble on a flat, level surface.

C. A marble in the bottom of a spherical bowl.

You are watching a science fiction movie where people on a space ship are traveling around the universe observing stars with different temperatures. Which of the following stars has the lowest surface temperature? A. A bluish star B. A yellowish star C. A reddish star D. The sun

C. A reddish star

Water weighs about 10 N per liter. A 4.0 kg ball floats on the water's surface. What is the weight of the water being displaced by the ball? A. Much less than 2000 N B. Much more than 40 N C. About 40 N D. Not enough information is given

C. About 40 N

The loudness of a sound is most related to its A. Frequency B. Wavelength C. Amplitude (Intensity) D. Period.

C. Amplitude (Intensity)

Suppose you go from the earth to a planet where the acceleration of gravity is 2.5 m/s2. On the new planet, your weight will be about A. The same as B. Double C. Be 1/4 its value on Earth D. Quadruple

C. Be 1/4 its value on Earth

Consider a high-speed bus colliding head-on with an innocent bug. The force of impact splatters the unfortunate bug over the windshield. Which is greater, the force on the bug or the force on the bus? A. Bus B. Bug C. Both are the same D. Can't say

C. Both are the same

Low-pitched sounds have A. Low frequencies B. Long periods C. Both of these D. None of these.

C. Both of these

Which action will give you more momentum toward the north: throwing one shoe southward at 10 m/s or two shoes southward at 5 m/s? A. Additional information is needed. B. One shoe southward at 10 m/s. C. Both will give the same momentum. D. Two shoes southward at 5 m/s.

C. Both will give the same momentum.

As shown in the figure, a bimetallic strip, consisting of metal G on the top and metal H on the bottom, is rigidly attached to a wall at the left. The coefficient of linear thermal expansion for metal G is greater than that of metal H. If the strip is uniformly heated, it will A. Bend in the middle B. Remain horizontal, but get longer C. Curve downward D. Curve upward E. Remain horizontal, but get shorter.

C. Curve downward

An ideal gas undergoes expansion without changing it's internal energy. During this process, its entropy A. Remains unchanged B. Increases C. Decreases D. Cannot be predicted from the data given

C. Decreases

You are playing with your younger cousins and find yourself on all fours, with your hands and feet on four bathroom scales on the level ground. You took a "Physics in Everyday Life" course so you can make A. A reasonable guess that the reading on each scale is obtained by your mass. B. Dividing your mass by 4. C. Dividing your weight by 4. D. Dividing your weight by 2.

C. Dividing your mass by 4.

Which of the following quantities is not conserved? A. Energy B.Angular momentum C. Entropy D. Momentum

C. Entropy

In order to do a positive amount of work you must A. Exert a force or move B. Exert a force and just move C. Exert a force and move in the direction of the force D. Change an object's position

C. Exert a force and move in the direction of the force

The force that accelerates a rocket in outer space is exerted on the rocket by the A. Rocket's wings B. Atmospheric pressure C. Exhaust gases D. Rocket's engine E. None of the above

C. Exhaust gases

Neglect air resistance in this question. If you drop a ball from a height of 4.9 m, it will hit the ground 1 s later. If you fire a bullet exactly horizontally from a height of 4.9 m, it will also hit the ground 1 s later. Explain. A. This is not true. The dropped ball will hit the ground first. B. This is not true. The bullet will hit the ground first. C. Gravity acts only in the vertical direction. D. The earth's curvature beneath the bullet compensates for its slower time of fall.

C. Gravity acts only in the vertical direction.

You are taking a shower in your dormitory when someone flushes a toilet nearby. The pressure in the cold water line drops and you find yourself showering in what feels like molten lava. This loss of cold water pressure occurs when the toilet lets cold water flow through the pipes delivering it to the bathroom and the water's speed in those pipes increases. Assuming all the piping to be about on the same level, the cold water's faster motion in the delivery pipes reduces its pressure in the shower head because faster moving water... A. Losses more energy to viscous drag as it flows through the delivery pipes. B. Has less gravitational potential energy than slower moving water. C. Has less pressure than slower moving water. D. Has less kinetic energy than slower moving water.

C. Has less pressure than slower moving water.

Why does the handle of a metal spoon submerged in boiling soup feel hot? A. From the soup is transferred through the spoon by convection B. The spoon has given up all its cold to the soup C. Heat from the soup is transferred through the spoon by conduction D. Heat from the soup is transferred through the spoon by radiation.

C. Heat from the soup is transferred through the spoon by conduction

Why does an ice cube feel cold? A. Heat from your hand enters the cube by convection B. Cold from the cube enters your hand by convection C. Heat from your hand enters the cube by conduction D. Cold from the cube enters your hand by conduction.

C. Heat from your hand enters the cube by conduction

Flowing honey is less likely to become turbulent than flowing water because... A. Water's large pressure favors turbulent flow. B. Water's large viscosity favors turbulent flow. C. Honey's large viscosity favors laminar flow. D. Honey's large density favors laminar flow.

C. Honey's large viscosity favors laminar flow.

The speed of a bullet fired from a gun will be about the same as the speed of the recoiling gun A. When both velocity and momentum are conserved B. Because velocity is conserved C. If the masses of the bullet and gun are equal D. When momentum is conserved E. None of the above

C. If the masses of the bullet and gun are equal

A child is riding a bike and skids to a stop. What happens to their kinetic energy? A. It is turned into potential energy B. It is conserved C. It is dissipated by static friction D. It is turned into heat by sliding friction

C. It is dissipated by static friction

Suppose you have a car traveling down the road at constant speed and not changing direction. It is experiencing gravity, wind resistance and frictional forces from the road. What can be said about the car's acceleration? A. It is not accelerating because it is not changing direction B. It is accelerating because it has constant velocity C. It is not accelerating because it has constant velocity D. It is not accelerating because gravity holds it down.

C. It is not accelerating because it has constant velocity

Falling into a leaf pile is much more comfortable than falling onto the bare ground. In both cases you come to a complete stop, so why does the leaf pile feel so much better? A. Hitting the ground involves a bigger impulse than hitting the leaves. B. The stopping time for hitting the ground is bigger. C. It takes more time to come to rest falling in a leaf pile, so the stopping force is less. D. The soft leaves cushion your fall.

C. It takes more time to come to rest falling in a leaf pile, so the stopping force is less.

Your body is presently converting chemical potential energy from food into thermal energy at a rate of about 100 J/s, or 100 W. If heat were flowing out of you at a rate of about 200 W, what would happen to your body temperature? A. It would remain constant. B. It would increase. C. It would decrease. D. More information is needed to be able to answer.

C. It would decrease.

An object is in stable equilibrium only when A. Its total potential energy lowers whenever it reorients. B. It is not moving C. Its total potential energy rises whenever it reorients. D. It is moving

C. Its total potential energy rises whenever it reorients.

Compared to planets close to the sun, and based upon Kepler's third law of planetary motion, the length of the year of planets farther out from the sun are A. The same B. Less C. Larger D. More information is necessary.

C. Larger

Lead sinkers actually float on the surface of liquid mercury. Which takes up more space: 1 kg of mercury or 1 kg of lead? A. Not enough information is given B. Neither take up any space C. Lead D. Mercury

C. Lead

What does the period of a pendulum depend on? A. Mass and gravity B. Length and mass C. Length and gravity D. Mass, length and gravity

C. Length and gravity

An astronaut in deep space, far from any planet or star, has A. Weight but not mass. B. Both mass and weight. C. Mass but not weight. D. either mass nor weight.

C. Mass but not weight.

In a collision between bumper cars: A. Force is transferred from one car to the other. B. The force of momentum is conserved. C. Momentum is transferred from one car to the other. D. One car gains impulse and the other loses impulse.

C. Momentum is transferred from one car to the other.

If a golf ball were smooth rather than dimpled, it would... A. Curve toward the left after being hit by the club of a right-handed golfer. B. Curve toward the right after being hit by the club of a right-handed golfer. C. Not travel as far after being hit by a golf club. D. Travel much too far after being hit by a golf club.

C. Not travel as far after being hit by a golf club.

What can you say about the pressures at points 1 and 2? A. P1 < P2 B. P1 > P2 C. P1 = P2 D. Can't be determined, needs more information

C. P1 = P2

By what primary heat transfer mechanism does the sun warm the earth? A. Conduction B. Convection C. Radiation D. All of the above processes are equally important in combination.

C. Radiation

Dimples on a golf ball hit without spin... A. Result in purely laminar flow B. Increase drag C. Reduce drag D. Are merely decorative

C. Reduce drag

Why is it hard to start the wheel of a roulette table spinning, and what keeps it spinning once it's started? A. Air resistance makes it hard to start, but the resistance goes away once the wheel is up to speed due to its streamlining. B. Friction makes it hard to start, but the friction goes away once it's up to speed. C. Rotational inertia, as measured by rotational mass. D. Inertia, as measured by mass.

C. Rotational inertia, as measured by rotational mass.

When a spinning skater pulls in her arms: A. She increases her angular momentum. B. Her kinetic energy is conserved. C. She decreases her rotational mass. D. She increases her angular impulse.

C. She decreases her rotational mass.

Rolling involves: A. Sliding friction. B. Both static and sliding friction. C. Static friction. D. No friction.

C. Static friction.

If you try to cook vegetables in 100 °C air, it takes a long time, but if you cook those same vegetables in 100 °C steam, they cook quickly. Why does the steam transfer so much more heat to the vegetables? A. Steam conducts heat better than air. B. The steam is hotter than the air. C. Steam has a higher heat capacity than air. D. The vegetables absorb the steam, since steam is water vapor.

C. Steam has a higher heat capacity than air.

In which of these materials does sound travel fastest? A. Air B. Water C. Steel D. All the same at the same temperature

C. Steel

For the particular medium, the speed of sound varies with A. Amplitude B. Frequency C. Temperature D. All of these.

C. Temperature

Newton's Second Law of Motion says... A. The bigger the force the bigger the mass. B. Mass is proportional to acceleration. C. The bigger the force the bigger the acceleration. D. The bigger the mass the bigger the acceleration.

C. The bigger the force the bigger the acceleration.

Some scientists assert that there would be no life on earth if ice did not have a molecular structure with a lot of open space because A. Ice would be denser than water and having a solid sink in its own liquid form would violate the conservation of energy. B. Ice would be less dense than it is now and float too much C. The density of ice would be greater than water and lakes would freeze solid - from the bottom up. D. Ice would be so light that it could never form, leaving too much water on the Earth's surface.

C. The density of ice would be greater than water and lakes would freeze solid - from the bottom up.

Suppose you have two cars, and the larger one is twice as massive as the smaller one. If you and a friend push on them so that their accelerations are equal, how must the forces applied to the cars compare? A. The force on the larger car is equal to that on the smaller car B. The force on the larger car is ½ that on the smaller car C. The force on the larger car is twice that on the smaller car D. The force on the larger car is more than three times that on the smaller car.

C. The force on the larger car is twice that on the smaller car

Equilibrium occurs when: A. An object is motionless. B. All the forces on an object are equal. C. The forces on an object are balanced. D. There are no forces acting on an object.

C. The forces on an object are balanced.

What causes knocking in your car's engine? A. The piston compresses the fuel / air mixture so that it is a liquid and the piston hits it. B. The fuel ignites in the exhaust system. C. The fuel ignites before it should. D. A connecting rod bearing is loose.

C. The fuel ignites before it should.

As you begin pedaling your bicycle and it accelerates forward, the forward force that the bicycle needs to accelerate is exerted by A. The tires on the ground. B. The pedals on your feet. C. The ground on the tires. D. Your feet on the pedals.

C. The ground on the tires.

A difficult-to-open jar may open easily after being run under hot water for a moment. Explain A. The water lubricates the lid B. The heat from the water makes the lid expand and loosen C. The heat from the water causes the air inside the jar to expand, exerting pressure on the lid D. This doesn't really work; the effect is really an old wives' tale.

C. The heat from the water causes the air inside the jar to expand, exerting pressure on the lid.

In making ice cream, the flavored cream is in a container in contact with ice. In order to freeze the ice cream why is it essential to make the ice melt at a very low temperature? A. Liquid water has a high specific heat B. The melted ice makes it easier for the air to remove energy from the ice cream C. The low temperature of the ice as well as its melting removes energy from the flavored cream, causing it to freeze D. It is easier to stir things around with the ice melted

C. The low temperature of the ice as well as its melting removes energy from the flavored cream, causing it to freeze

When cooking a potato in a conventional oven it is useful to stick a nail in it, which makes it cook faster. This is because A. The nail is a good radiator of heat B. The nail promotes convection in the potato C. The nail is a good conductor of heat D. The nail gets much hotter than anything in the oven

C. The nail is a good conductor of heat

What is the center of mass of an object? A. The point at the exact center of the object B. The point where the object is pivoted when it rotates C. The point around which the object will rotate if it is free of outside torques D. The point where all the torques are balanced

C. The point around which the object will rotate if it is free of outside torques

A hurricane or gale force wind can lift the roof off a house, even when the roof has no exposed eaves. How can wind blowing across a roof produce an upward force on it? A. Drag forces on the roof drag the roof upward off the house. B. The wind catches the edge of the roof and blows it off. C. The rapidly-moving air above the roof is at a lower pressure than the still air inside the house. D. A flat roof is perfectly streamlined and this causes a lift force.

C. The rapidly-moving air above the roof is at a lower pressure than the still air inside the house.

You are hired as an engineer at a thermometer factory. Suppose you built a water thermometer by replacing the mercury in a mercury thermometer with water. You want to measure temperatures above freezing with it. How would it behave as the temperature drops from 5o C to 1o C? A. The reading will steadily decrease. B. The reading will steadily increase C. The reading will decrease and then begin increasing. D. The reading will increase and then begin decreasing.

C. The reading will decrease and then begin increasing.

You have a roll of papered foil that is shiny on one side and black on the other. You wrap a hot potato in that foil. Which side should be facing outward to keep the potato hot longest? A. It doesn't matter which side. B. The black side. C. The shiny side.

C. The shiny side.

Soil heats up much faster than water when the two are exposed to sunlight. Use that fact and your understanding of heat transfer to predict which way the wind will blow near the surface of the earth as the sun rises near the seashore. A. The surface wind will blow steadily in one direction along the shore, parallel to the boundary between land and water. B. The surface wind will blow from the land toward the water. C. The surface wind will blow from the water toward the land. D. The surface wind will blow alternately back and forth along the shore, parallel to the boundary between land and water. It will reverse directions every few minutes.

C. The surface wind will blow from the water toward the land.

Which of the following statements best describes the law of conservation of energy? A. Energy can change between many different forms, such as potential, kinetic, and thermal, but it is ultimately destroyed B. An object always has the same amount of energy C. The total quantity of energy in the universe never changes D. The fact that you can fuse hydrogen into helium to produce energy means that helium can be turned into hydrogen to produce energy E. It is possible for an object to gain or lose potential energy, because energy cannot be destroyed.

C. The total quantity of energy in the universe never changes

Driving down the road, you hit an insect. How does the force your car exerts on the insect compare to the force the insect exerts on the car? A. The force the insect exerts on the car is less. B. The insect exerts no force on the car C. The two forces are equal in magnitude. D. The force the car exerts on the insect is less.

C. The two forces are equal in magnitude.

You are holding two identical-looking balloons, one filled with air and one filled with water. You drop these two balloons from a very tall bridge and notice that the water-filled balloon hits the ground first because it traveled faster. The object that experienced the larger amount of drag is A. Neither balloon, as it was the same for both B. Neither balloon, as there is no drag force on an object moving at constant speed C. The water - filled balloon because it moved faster D. The air filled balloon because it slowed down more.

C. The water - filled balloon because it moved faster

Tapping your toothbrush on the sink dries it off because A. The force of the tapping knocks it off. B. The heat generated by the tapping loosens the water. C. The water on the toothbrush has inertia. D. The vibration of the tapping lowers the friction between the water and the toothbrush.

C. The water on the toothbrush has inertia.

For an object that is floating on a fluid, A. The weight of fluid displaced is less than its weight B. The weight of the fluid displaced is greater than the object's weight C. The weight of the fluid displaced equals the object's weight D.The weight of the object becomes less than in air.

C. The weight of the fluid displaced equals the object's weight

A spaceship is moving past us at a speed close to the speed of light. How would we view time (clocks) on the spaceship as it goes by? A. Time is the same for everyone B. Their clocks are going exactly half as fast as ours C. Their clocks are going slower than ours D. Their clocks are going at the same rate as ours E. Their clocks are going faster than ours.

C. Their clocks are going slower than ours

When atoms bind in a chemical reaction,... A. They are gaining some thermal energy. B. They are gaining some potential energy. C. They are giving up some potential energy. D. They are converting thermal energy into potential energy.

C. They are giving up some potential energy.

When you ride your scooter you have momentum. When you ride twice as fast you have A. Almost twice the momentum B. Four times the momentum C. Twice the momentum D. None of the above

C. Twice the momentum

You open the refrigerator in your room and put in a case of room-temperature root beer. After an hour, the root beer is ice cold. If your room air did not exchange any heat with the outdoor air during that time, the room air will be... A. Colder because the refrigerator reverses natural heating, so that things get colder rather than hotter B. Colder because as the refrigerator struggles to cool the root beer, some of the cold it produces inevitably leaks out into the room as the result of imperfect insulation C. Warmer because the refrigerator will have pumped heat out of the root beer and into the room air D. Warmer because some of the heat from the root beer inevitably leaks out into the room as the result of imperfect insulation.

C. Warmer because the refrigerator will have pumped heat out of the root beer and into the room air

Why are failures in dams more likely to occur closer to the bottom of the dam? A. Water is considerably more dense at the bottom. B. The temperature is higher at the bottom. C. Water pressure is higher at the bottom. D. Water weighs more at the bottom.

C. Water pressure is higher at the bottom.

Under what conditions are the values of average speed and the magnitude of the average velocity equal? A. When moving in a straight line B. When moving in a circular path C. When moving in a straight line and not turning around D. When walking around the perimeter of a rectangle

C. When moving in a straight line and not turning around

If you block the outlet of a hand bicycle pump and push the handle inward to compress the air inside the pump, the pump will become warmer. Why? A. You are putting heat into the pump. B. By blocking the outlet you are preventing the heat from escaping the pump. C. You are doing work on the air in the pump. D. Compressed air is always warmer.

C. You are doing work on the air in the pump.

Your weight and mass are different in that A. Your weight is measured in kg but not your mass B. Your mass depends upon local gravity but your weight does not C. Your weight depends upon local gravity but your mass does not D. Being weightless means that you have to lose mass

C. Your weight depends upon local gravity but your mass does not

Two teams are having a tug-of-war with a sturdy rope. It has been an even match so far, with neither team moving. What is the net force on the left team? A. Away from the right team B. Toward the right team C. Zero D. Both toward and away from the right team

C. Zero

A speedboat is pulling a water-skier with a rope, exerting a large forward force on her. The skier is traveling in a straight line at constant speed. The net force she experiences is A. In the backward direction. B. Both forward and backward. C. Zero. D. In the forward direction.

C. Zero.

The value of the average velocity for any round trip is equal to A. The person's speed halfway through the path. B. Total distance traveled divided by total trip time. C. Zero. D. The final acceleration multiplied by trip time.

C. Zero.

Bolts work because they act like very strong springs and extend slightly when they are tightened. Suppose a steel bolt has spring constant 1.8x108N/m. How far would it have to stretch in order to provide a force 2000N? A. 1.8x10-3m B. 1.8x10-8m C. 1.11 m D. 1.11x10-5m

D. 1.11x10-5m

If you double the absolute temperature of a star, its power output increases by a factor of... A. 2 B. 4 C. 8 D. 16

D. 16

A gymnast jumps upward with an initial speed of 10 m/s. She is in the air for a total time of about A. 5 seconds B. 10 seconds C. 1 second D. 2 seconds

D. 2 seconds

An object of mass 10 kg was moving with a Speed = 2 m/s) . You tried to stop (applied a force) for 4 seconds and the object was stopped. What is the initial kinetic energy of the object? A. 10 J B. 200 J C. 40 J D. 20 J

D. 20 J

The temperature changes from 35°F during the night to 75°F during the day. What is the temperature change on the Celsius scale? A. 40 C° B. 32 C° C. 72 C° D. 22 C°

D. 22 C°

What is the potential energy of a 40 kg box that is 6 m above the ground? A. 6 J B. 60 J C. 240 J D. 2400 J

D. 2400 J

How much heat is required to raise the temperature of a 225-g lead ball from 15.0°C to 25.0°C? The specific heat of lead is 128 J/kg · K A. 145 J B. 576 J C. 725 J D. 288 J E. 217 J

D. 288 J

A net force of 8 N is applied to a 2 kg object. The object's acceleration is A. 16 m/s2 B. 2 m/s2 C. 8 m/s2 D. 4 m/s2

D. 4 m/s2

The brake system in most cars makes use of a hydraulic system. This system consists of a fluid filled tube connected at each end to a piston. Assume that the piston attached to the brake pedal has a cross sectional area of one half a square inch and the piston attached to the brake pad has a cross section area of two square inches. When you apply a force of 10 pounds to the piston attached to the brake pedal, the force at the brake pad will be, A. 5 pounds B. 10 pounds C. 20 pounds D. 40 pounds

D. 40 pounds

The rest energy of a 60 kg person is A. 1.8 × 1010 J B. 8.4 × 1018 J C. 9 × 1016 J D. 5.4 × 1018 J

D. 5.4 × 1018 J

If your mass is 60 kg on Earth, what would your mass be on the Moon? A. 60 lb B. 0 kg C. 10 lb D. 60 kg E. 10 kg

D. 60 kg

You are bored during the summertime when school is not in session and you decide to do an experiment where you compare the properties of water and air. If the density of air is 1.25 kg/m3and the density of water is 1000 kg/m3, what volume of air weighs the same as 1 liter of water? A. 0.00125 liters B. 1.25 liters C. 125 liters D. 800 liters

D. 800 liters

The diameter of a pipe is tripled while the pressure difference across the pipe remains the same. The volume flow rate of the pipe increases by a factor of... A. 9 B. 3 C. 27 D. 81

D. 81

Suppose you weigh 986 N. How much force does the Earth exert on you, if any? A. None B. It cannot be determined C. 98.6N D. 986 N

D. 986 N

If you are riding in an elevator descending at constant speed, what are the forces acting on you? A. There are no forces acting on you. B. A downward weight and a smaller upward force from the floor of the elevator. C. A downward weight and a downward force from the floor of the elevator. D. A downward weight and an equal upward force from the floor of the elevator.

D. A downward weight and an equal upward force from the floor of the elevator.

The vessels shown below all contain water to the same height. Rank them according to the pressure exerted by the water on the vessel bottoms, least to greatest. A. 1, 2 ,3, 4 B. 4, 3, 2, 1 C. 3, 4, 2, 1 D. All pressure are the same

D. All pressure are the same

A baseball player balances a bat on his finger; the bat is laying sideways and not standing on end. The bat will balance A. Near the end of its handle B. Near the end farthest from the handle C. At its middle D. At its center of mass

D. At its center of mass

A child throws a ball perfectly horizontally at the same time a dirt clod falls off it at the same height above the ground. The clod falls vertically downward. Ignoring air resistance, the time when the clod hits the ground will A. Be earlier than when the ball hits not depend upon how high it started B. Falling from C. Be later than when the ball hits D. Be equal to the time the ball hits the ground

D. Be equal to the time the ball hits the ground

Why are black steam radiators better at heating a room than radiators that have been painted white or silver? A. Black absorbs heat better than white. B. Black is the hottest color. C. Air circulates better with a black radiator. D. Black is the best color for emitting thermal radiation.

D. Black is the best color for emitting thermal radiation.

When you kick a soccer ball, which pushes on the other harder: your foot or the soccer ball? A. The answer depends on additional factors not mentioned here. B. Your foot pushes harder. C. The soccer ball pushes harder. D. Both push equally.

D. Both push equally.

The first law of thermodynamics is a re - statement of the law ofA. AveragesB. Thermal equilibriumC. Conservation of momentumD. Conservation of energy

D. Conservation of energy

Hot air rising is an example of which of the following? A. Conduction B. Induction C. Radiation D. Convection

D. Convection

What two properties of a material affect the speed of sound in the material? A. Buoyant force and density B. Specific heat and density C. Density and volume D. Density and phase.

D. Density and phase.

The entropy of an isolated system A. Always increases B. Always decreasesC. Remains constant D. Either increases or remains constant E. Either decreases or remains constant

D. Either increases or remains constant

In order to do a negative amount of work you must A. Exert a force and move in the direction of the force. B. Exert a force or move. C. Change an object's position. D. Exert a force and move opposite to the direction of the force.

D. Exert a force and move opposite to the direction of the force.

As a planet moves in an elliptical orbit around its star, it speed is A. Faster as it is moving closer to the star and slower as it moves further away. B. Constant. C. Fastest when it is furthest from the star. D. Fastest when it is closest to the star.

D. Fastest when it is closest to the star.

As the Reynolds number decreases,... A. Flow is becoming more laminar. B. Flow is slowing down. C. Flow is speeding up. D. Flow is going from being viscous dominated to inertia dominated and therefore turbulent.

D. Flow is going from being viscous dominated to inertia dominated and therefore turbulent.

As the Reynolds number increases,... A. Flow is becoming more laminar. B. Flow is speeding up. C. Flow is slowing down. D. Flow is going from being viscous dominated to inertia dominated and therefore turbulent.

D. Flow is going from being viscous dominated to inertia dominated and therefore turbulent.

Force and momentum are related in that: A. Momentum and force both have the same units B. Momentum times force equals a constant. C. Momentum is a change in force per unit time D. Force is a change in momentum per unit time

D. Force is a change in momentum per unit time

Heat naturally flows A. From a region of higher entropy to a region of lower entropy. B. From a region of lower temperature to a region of higher temperature. C. From a region of lower entropy to a region of higher entropy. D. From a region of higher temperature to a region of lower temperature.

D. From a region of higher temperature to a region of lower temperature.

Consider the Moon orbiting the Earth. _______ is the centripetal force for the orbit, and one could therefore measure the mass of the ________ by studying the Moon's orbit. A. Drag; Earth B. Tension; Moon C. Gravity; Moon D. Gravity; Earth

D. Gravity; Earth

Suppose you have two containers with liquid in them. One has a density of 760 kg/m3and the other has a density of 910 kg /m3. If an object floats in one container and sinks in the other, the density of the object A. Has a value equal to the difference in densities of the two liquids B. Must have a value equal to the average densities of the two liquids C. Has a value less than 760 kg/m3or greater than 910 kg/m3 D. Has a value between 760 kg/m3and 910 kg/m3

D. Has a value between 760 kg/m3and 910 kg/m3

The neighborhood children are playing and one has lost a pocketful of change. As a result they all decide to do a close inspection of the sidewalk. They notice that there are gaps in between the sidewalk filled with a felt - like material. These gaps will prevent... A. High stress due to brittleness B. High stress due to the weight of the sidewalk C. High stress due to electron "collisions" D. High stress due to thermal expansion.

D. High stress due to thermal expansion.

Your class is rather unhappy with the instructor, and they pitch in and decide to fund a sabbatical for him to go to Mars. Unbeknownst to the students the following semester, the instructor has made long distance course arrangements so the "show can go on". The instructor begins talking about mass, weight and related things. He correctly makes which following statement: A. His weight and mass have both changed significantly. B. Neither his weight nor his mass have changed much. C. His weight is still essentially unchanged but his mass is less than on earth. D. His mass is still essentially unchanged but his weight is less than on earth.

D. His mass is still essentially unchanged but his weight is less than on earth.

If the absolute temperature of an object is tripled, the thermal power radiated by this object (assuming that its emissivity and size are not affected by the temperature change) will A. Increase by a factor of 18 B. Increase by a factor of 27 C. Increase by a factor of 3 D. Increase by a factor of 81 E. Increase by a factor of 9

D. Increase by a factor of 81

Suppose your car is traveling at a certain speed on a very slick road. All of a sudden you step on the accelerator and the back wheels begin to spin but the car remains at the same speed. The kinetic energy of the car A. Remains the same. B. Is all converted to disordered energy. C. Decreases. D. Increases because of the increased rotation of the tires.

D. Increases because of the increased rotation of the tires.

A propeller works because... A. It clears the air away from the front of the plane. B. It is a system of rotating wings. C. It decreases the induced drag. D. It generates lift forces in the forward direction.

D. It generates lift forces in the forward direction.

A Diesel engine is more efficient that a gasoline engine because A. It has a lower temperature and can therefore convert more heat into work. B. It has a higher temperature and can therefore convert less heat into work. C. It has a lower temperature and can therefore convert less heat into work. D. It has a higher temperature and can therefore convert more heat into work.

D. It has a higher temperature and can therefore convert more heat into work.

When you throw a hot rock into a cold puddle, what happens to the overall entropy of the system? A. It decreases. B. More information is needed. C. It remains constant. D. It increases.

D. It increases.

Suppose you have a car traveling down the road at constant speed and not changing direction. It is experiencing gravity, wind resistance and frictional forces from the road. What can be said about the car's acceleration? A. It is accelerating because there are forces acting on it B. It accelerating because the motor is running, propelling the car forward C. It is not accelerating because gravity holds it down D. It is not accelerating because it has constant velocity

D. It is not accelerating because it has constant velocity

An elevator is moving downward and coming to a stop. What is its acceleration, if any? A. Its acceleration is zero. B. It is not accelerating, it is decelerating. C.Its acceleration is downward. D. Its acceleration is upward.

D. Its acceleration is upward.

When a fish hovers over the bottom of a lake, what forces act on it, and what is the net force? A. Lift only, for a net force up B. Lift only, for a net force zero C. Lift and weight, for a net force up D. Lift and weight, for a net force zero

D. Lift and weight, for a net force zero

The SI units of acceleration are A. M/s B. Kg m2/s2 C. Kgm/s2 D. M/s2

D. M/s2

When a 134-Hz tuning fork and a 144-Hz tuning fork are struck, the beat frequency is A. 2 Hz B. 6 Hz C. 8 Hz D. More than 8 Hz

D. More than 8 Hz

A fan can be used to circulate air around a room. The pressure at the inlet side of the fan is A. Less than the pressure at the outlet side and less than atmospheric pressure B. Less than the pressure at the outlet side but more than atmospheric pressure C. Equal to the pressure at the outlet side D. More than the pressure at the outlet side

D. More than the pressure at the outlet side

Suppose you are driving your car down the highway and speeding up. Which of the following are true? A. The car's momentum is constant but not its kinetic energy B. The car's kinetic energy is constant but not its momentum C Both the car's kinetic energy and momentum are constant D. Neither the car's kinetic energy nor momentum are constant

D. Neither the car's kinetic energy nor momentum are constant

An important feature of the Carnot cycle is that A. Its efficiency is determined by the temperatures of the hot and cold reservoirs between which it works and by the properties of the working substance used, and on nothing else B. Its efficiency depends only on the absolute temperature of the hot reservoir used C. It is an example of an irreversible process that can be analyzed exactly without approximations D. No engine can be more efficient than a Carnot engine operating between the same two temperatures E. Its efficiency can be greater than 100%.

D. No engine can be more efficient than a Carnot engine operating between the same two temperatures

Which type of heat transfer can happen efficiently through empty space? A. Conduction B. Evaporation C. Convection D. Radiation

D. Radiation

The greenhouse effect affects the Earth by A. Increasing the amount of energy received from the sun. B. Trapping gases with high heat capacity in the atmosphere. C. Reducing the average temperature of the planet. D. Raising the average temperature of the planet.

D. Raising the average temperature of the planet.

If the distance between planets is somehow doubled, the force of gravity between them would A. Doubles B. Quadruples C. Reduces by half D. Reduces by one quarter.

D. Reduces by one quarter.

On a humid summer day, perspiration does not cool you off much. Why? A. The air density is extremely low and the air pressure is too high to permit water to evaporate B. The water vapor in the air is moving too fast to condense on your skin as perspiration C. The air density is extremely low and its pressure is too low to permit water to evaporate D. The air is almost saturated with water vapor and there is almost no net evaporation

D. The air is almost saturated with water vapor and there is almost no net evaporation

A salad spinner is a rotating basket that dries salad after washing. How does the spinner extract the water? A. The spinner's inertia means it naturally tends to moves in a straight line B. The water is pushed outward by its acceleration through the holes in the basket C. The water is pushed outward by centrifugal force through the holes in the basket D. The apparent weight of the water is outward, forcing it through the holes in the basket

D. The apparent weight of the water is outward, forcing it through the holes in the basket

Fluids have viscosity because... A. Molecules in fluids are long and get tangled. B. The atoms and molecules within the fluid are heavy and hard to push.. C. They are always in contact with some boundary. D. The atoms and molecules within the fluid interact with each other, producing internal frictional forces.

D. The atoms and molecules within the fluid interact with each other, producing internal frictional forces.

Cars are designed so that their bodies buckle (permanently deform) when they are in an accident. How does the buckling make the car safer by not allowing it to recoil (bounce) so much? A. The buckling stores energy. B. The buckling gives the car a high coefficient of restitution. C. The buckling provides energy to the crashing objects. D. The buckling dissipates the energy of the crash.

D. The buckling dissipates the energy of the crash.

When you sit facing a campfire outdoors, your face feels quite warm because A. Microwaves from the moving charged particles heat your skin B. Convection from the fire is carrying hot air sideways to your face C. Conduction in the air is carrying heat from the flames to your skin D. The campfire is radiating heat towards your skin

D. The campfire is radiating heat towards your skin

A car engine runs most efficiently when A. The engine temperature is hot and it is a hot summer day. B. The engine temperature is not too high and it is a cold winter day. C. The engine temperature is not too high and it is a hot summer day. D. The engine temperature is hot and it is a cold winter day.

D. The engine temperature is hot and it is a cold winter day.

Suppose you have two cars, and the larger one is twice as massive as the smaller one. If you and a friend push on them so that their accelerations are equal, how must the forces applied to the cars compare? A. The force on the larger car is three times that on the smaller car B. The force on the larger car is equal to that on the smaller car C. The force on the larger car is half that on the smaller car D. The force on the larger car is twice that on the smaller car

D. The force on the larger car is twice that on the smaller car

Why can't you open a door by pushing on its hinged side? A. Actually, you can if the force is big enough. B. The force in this case is zero. C. The force here is parallel to the lever arm, not perpendicular. D. The lever arm is zero.

D. The lever arm is zero.

When water flows through a pipe and the pipe becomes smaller in diameter,... A. The pressure increases and the speed increases B. The pressure decreases and the speed decreases C. The pressure increases and the speed decreases D. The pressure decreases and the speed increases

D. The pressure decreases and the speed increases.

Considering the airflow around an airplane's wings,​... A. The air speed is higher below the wing. B. The pressure is higher above the wing. C. The air speed is lower above the wing. D. The pressure is lower above the wing.

D. The pressure is lower above the wing.

The acceleration of an object is equal to A. The rate of change of its speed only B. The rate of change of its position C. The time an object has been in motion D. The rate of change of its velocity

D. The rate of change of its velocity

Suppose an object is traveling at terminal velocity, so it is falling through air but not accelerating. How does the force of air resistance compare to its weight? A. Air resistance is less than the ball's weight. B. The two forces are equal. C. Air resistance is greater than the ball's weight. D. The two forces are equal and opposite.

D. The two forces are equal and opposite.

The dimples on a golf ball help the ball fly farther because... A. They decrease the turbulence. B. They increase the Reynolds number. C. They decrease the Reynolds number. D. They trip the boundary layer into becoming turbulent.

D. They trip the boundary layer into becoming turbulent.

Clothing works to help keep humans warm by A. Trapping a layer of motionless air next to the skin, reducing conduction. B. Reducing the rate of convection off of the skin. C. Absorbing heat radiated off by the body, if the clothing is light-colored. D. Trapping a layer of motionless air next to the skin, reducing convection

D. Trapping a layer of motionless air next to the skin, reducing convection

Cities have to use water towers to supply water to because A. The water tower has a vault of air that is pressurized B Water moves fastest at the bottom of the water tower and this speed is transmitted uniformly throughout all water pipes below C. Water pressure at the top of the tower is transmitted through the water pipes D. Water pressure at the bottom of the tower is much higher than at the top.

D. Water pressure at the bottom of the tower is much higher than at the top.

A common glass thermometer contains a red or silver liquid that rises upward in a glass tube as the temperature of the thermometer increases. The liquid moves up the tube because A. Only the glass contracts as its temperature decreases, so the liquid moves up the tube to occupy more of the tube's internal space B. While both the glass and the liquid contract as their temperatures increase, the glass contracts more rapidly than the liquid does C. The pressure of gas above the liquid decreases as its temperature rises and the liquid is sucked upward in the glass tube D. While both the glass and the liquid expand as their temperatures increase, the liquid expands more rapidly than the glass does.

D. While both the glass and the liquid expand as their temperatures increase, the liquid expands more rapidly than the glass does.

A net torque on an object ________________________ A. Will cause the rotational mass to change. B. Will cause the angular acceleration to change. C. Will cause translational motion. D. Will cause the angular velocity to change.

D. Will cause the angular velocity to change.

During one cycle, an automobile engine takes in 12,000 J of heat and discards 9000 J of heat. What is the efficiency of this engine? A. 400% B. 133% C. 75% D. 33% E. 25%

E. 25%

A machine uses 1000 J of electric energy to raise a heavy mass, increasing its potential energy by 300 J. What is the efficiency of this process? A. 100% B. 85% C. 70% D. 35% E. 30%

E. 30%

The illustration shows a thermometer that uses a column of liquid (usually mercury or ethanol) to measure air temperature. In thermal equilibrium, this thermometer measures the temperature of A. The column of liquid B. The glass that encloses the liquid C. The air outside the thermometer D. Both A and B E. All of A, B, and C

E. All of A, B, and C

A blacksmith usually hammers hot metal on the surface of a massive steel anvil. The reason this is more effective than hammering the hot metal on the surface of a thin steel plate is A. The anvil exerts more force on the hot metal. B. The massive anvil can absorb more heat than a thin steel plate. c. The massive anvil has more inertia.

c. The massive anvil has more inertia.

An unseatbelted driver can be injured by the steering wheel during a head-on collision. The driver hits the steering wheel when the car suddenly comes to a stop because A. Gravity makes the head move forward. B. The steering wheel is pushed back into the driver's head. C. The force of the collision pushes the D. D. Driver's head into the steering wheel. the driver's head has inertia.

the driver's head has inertia.

When the water from the sprayer hits the side of your house, it slows to a stop. If it hasn't lost any energy since leaving the sprayer, what is the pressure of the water at the moment it stops completely? Assume atmospheric pressure equal to 100,000 Pa.

100000Pa

The gravity of a black hole is so strong that not even light can escape from within its surface or "event horizon." Even outside that surface, enormous energies are needed to escape. Suppose that you are 6.00 km away from the center of a black hole that has a mass of 1.00x1031 kg. If your mass is 66.0 kg, how much do you weigh?

1222833333333333.2 N

Rather than putting a pump in the fountain, the town engineer puts a water storage tank in one of the nearby high-rise office buildings. How high up in that building should the tank be for its water to rise to 14 m when spraying out of the fountain? (Neglect friction.)

14m

To dive far below the surface of the water, a submarine must be able to withstand enormous pressures. At a depth of 151 m, what pressure does water exert on the submarine's hull? Use g=9.81 m/s2.

1581310Pa

Your new designer chair has an S-shaped tubular metal frame that behaves just like a spring. When your friend, who weighs 611 N, sits on the chair, it bends downward 3.00 cm. What is the spring constant for this chair?

20366.67 N/m

Engineers are trying to create artificial "gravity" in a ringshaped space station by spinning it like a centrifuge. The ring is 191 m in radius. How quickly must the space station turn in order to give the astronauts inside it apparent weights equal to their real weights at the earth's surface? Use g=9.81 m/s2.

43.29 m/s

You are swinging a tin can around your head in a perfectly horizontal circle of radius 4 m. (This is really not possible but we're saying it almost happens.) If the speed of the can is 4 m/s and its mass is 2 kg, what inward force is required to keep the can moving in the circle? A. 8 N B. 1/16 N C. 2 N D. 16 N

A. 8 N

Which system is in a state of stable equilibrium? A. A marble in the bottom of a spherical bowl B. A Marble on top of a spherical bowl C. A marble on a flat, level surface D. A marble rolling down an inclined surface.

A. A marble in the bottom of a spherical bowl

If you are standing at the outer edge of a rotating carousel, you are A. Accelerating toward the center. B. Not accelerating. C. Accelerating away from the center. D. Accelerating in the forward direction.

A. Accelerating toward the center.

Suppose you are standing on a bathroom scale when you are flying in a jet airplane. For a moment the scale reads more than your actual weight. During that moment, it's exerting an upward force on you that is greater than your weight and you are A. Accelerating upward B. Accelerating downward C. Not accelerating D. Accelerating sideways.

A. Accelerating upward

Your apartment window opens 20 meters (65 feet) above a lemonade stand. Your friend lowers a long plastic tube out the window until its end enters the tank of delicious lemonade far below. She then begins to suck on the other end of the tube in hopes of getting a free drink. To her dismay, she never tastes a drop because A. Atmospheric pressure cannot support a column of lemonade 20 meters tall B. Lemonade is too thick to pass through a tube that long C. The tube has an average density that is larger than that of lemonade, so the buoyant force cannot support its weight D. The tube's acceleration is downward, so it prevents the lemonade's velocity from being upward.

A. Atmospheric pressure cannot support a column of lemonade 20 meters tall

If the mass of one planet is somehow doubled, the force of gravity between it and a neighboring planet would A. Doubles B. Quadruples C. Reduces by half D. Reduces by one quarter

A. Doubles

Suppose you are standing on a bathroom scale when you are flying in a jet airplane. For a moment the scale reads less than your actual weight. During that moment, it's exerting an upward force on you that is A. Greater than your weight B. Equal to zero C. Equal to your weight D. Less than your weight.

A. Greater than your weight

The curves on bicycle racetracks are steeply banked, so that the inner edge of each curve is much lower than its outer edge. This banking tips the support force that the track exerts on the bicycle wheel toward the center of each turn. That center-directed or centripetal force on the bicycle is important because it A. Helps the bicycle accelerate inward to complete each turn without skidding B. It does work on the bicycle during each turn and thus increases the bicycle's energy C. Balances the outward centrifugal force that the bicycle experiences as it completes each turn, so that the bicycle experiences zero net force D. It does negative work on the bicycle during each turn and thus decreases the bicycle's energy.

A. Helps the bicycle accelerate inward to complete each turn without skidding

A hot air balloon rises because A. Its average density is less than air. B. It is lighter than air. C. Hot air is more buoyant than cold air. D. Hot air always rises.

A. Its average density is less than air.

If water in a level pipe begins moving faster, A. Its pressure decreases. B. Its pressure increases. C. Its pressure is unchanged. D. Its pressure may increase or decrease, depending on other factors.

A. Its pressure decreases.

An object is in stable equilibrium only when A. Its total potential energy rises whenever it reorients B. Its total potential energy lowers whenever it reorients C. It is not moving D. It is moving

A. Its total potential energy rises whenever it reorients

Compared to planets close to the sun, and based upon Kepler's third law of planetary motion, the length of the year of planets farther out from the sun are A. Larger B. The same C. Less D. More information is necessary.

A. Larger

In a soccer game, someone has kicked the ball so that it is heading right toward your face. You want to slow the ball down with your arm. To execute your plan most effectively you should A. Move your arm in the direction that the ball is moving. B. Move your arm rapidly toward the oncoming ball. C. Keep your arm still. D. ove your arm slowly toward the oncoming ball.

A. Move your arm in the direction that the ball is moving.

You are swinging a 2 kg tin can around your head in a perfectly horizontal circle of radius 1 m with a speed of 6 m/s. (This is really not possible but we're saying it almost happens.) If the string can safely exert a force of 30 N will it be able to swing the can? A. No because the required force is 36 N B. No because the required acceleration is 36 m/s2. C. Yes because only linear acceleration would break the string D. Yes because the weight of the can does not matter

A. No because the required force is 36 N

The pressure gradient set up in water standing is a glass is an example of ________ ________ in pressure, while variations in pressure due to water flowing faster in the smaller parts of a pipe are a type of ________ ________ in pressure. A. Static Variation; Dynamic Variation B. Static Variation; Buoyant Force C. Dynamic Variation; Dynamic Constancy D. Dynamic variation; Constant Value

A. Static Variation; Dynamic Variation

A three - wheeler is A. Statically stable and dynamically unstable B. Both statically and dynamically unstable C. Both statically and dynamically stable D. Statically unstable and dynamically stable

A. Statically stable and dynamically unstable

Why aren't there any thermometers that read temperatures down to -300 ºC? A. That would be lower than absolute zero. B. Making a thermometer to read that low would be prohibitively expensive. C. There is no substance that remains liquid at that low a temperature. D. There are; they are just extremely expensive.

A. That would be lower than absolute zero.

As you clear the sidewalk with a leaf blower, the blower pushes you away from the leaves. What is pushing on the blower so that it can push on you? A. The air coming out of the blower. B. The air surrounding the leaves. C. Nothing is pushing on the blower. It's just action/reaction. D. The force on the blower is the reaction to the force of you holding it.

A. The air coming out of the blower.

A helium-filled balloon floats in air. What will happen to an air-filled balloon in helium? Why? A. It will rise because helium is less dense than air. B. It will sink because air is denser than helium. C. It will neither rise nor sink because air and helium are both gases. D. It will sink because helium is denser than air.

B. It will sink because air is denser than helium.

The time it takes a relatively small object to orbit a much larger object doesn't depend on the mass of the small object. Use an astronaut who is walking in space near the space shuttle to illustrate that point. A. The astronaut and shuttle have vastly different masses, but both orbit the much-larger earth at the same rate. B. The shuttle orbits the earth, but the astronaut doesn't because he is much less massive than the shuttle. C. The shuttle orbits the earth, and the astronaut orbits the shuttle. D. The shuttle orbits the earth, but the astronaut doesn't orbit the shuttle.

A. The astronaut and shuttle have vastly different masses, but both orbit the much-larger earth at the same rate.

A rocket accelerates because A. The backward momentum of the exhaust gas is balanced by the forward momentum of the rocket. B. Its thrust pushes against the ground as it lifts off. C. The thrust is in the direction of the exhaust gas. D. Its exhaust gas pushes against the air.

A. The backward momentum of the exhaust gas is balanced by the forward momentum of the rocket.

You work with a catering firm and have been given a challenge. By emptying several liquid beverage dispensers, you have to rank them in order of their content (which one is fullest, next fullest, etc.) Having had a physics class, you devise a scheme to compare the speeds of the fluids exiting the spouts at the bottom of the containers. The principle you base your prediction on is: A. The pressure (and hence water level) is lower when the speed is lower. B. The volume is lower so the speed is lower. C. The speed increases when there is more air in the jug. D. What were you thinking!? The speeds won't depend upon fluid level

A. The pressure (and hence water level) is lower when the speed is lower.

The spin cycle in your washing machine partially dries clothes by spinning them in a perforated metal basket. Such a process works because A. The water leaves the basket moving tangent to the circular path B. The water is forced directly outward from the basket C. The water is drawn to the center of the basket D. The water is drained by gravity out the bottom of the basket

A. The water leaves the basket moving tangent to the circular path

Why do elastic balls bounce so well? A. They store energy through compression, like a spring. B. They are all filled with a special energy-absorbent liquid. C. They are always thrown well. D. They permanently deform, storing energy.

A. They store energy through compression, like a spring.

Suppose you are spending your weekend on roller skates trying to get momentum from somewhere. Which of the following will give you momentum in the north direction? A. Throwing your keys southward B. Throwing your keys northward C. Bending down and throwing your keys straight up D. (B) or (C)

A. Throwing your keys southward

Suppose you are spending your weekend on roller skates trying to get momentum from somewhere. Which of the following will give you momentum in the north direction? A. Throwing your keys southward. B. Throwing your keys northward. C. Bending down and throwing your keys straight up. D. (B) or (C).

A. Throwing your keys southward.

You are flying on an airplane and you notice that a ball of aluminum foil from lunch starts to roll to the left. From the motion of the foil ball you can conclude that the plane is A. Turning toward the right. B. Turning toward the left. C. Moving at constant velocity toward the right. D. Moving at constant velocity toward the left.

A. Turning toward the right.

You are riding a multi-speed bicycle up a steep hill that's 100 m high and want to do as little work as possible on your way up the hill. A. Your choice of gears doesn't matter because you'll do the same amount of work climbing the hill no matter which gear you choose. B. You should choose the largest crank sprocket (attached to the pedals) and the largest freewheel sprocket (attached to the rear wheel). C. You should choose the largest crank sprocket (attached to the pedals) and the smallest freewheel sprocket (attached to the rear wheel). D. You should choose the smallest crank sprocket (attached to the pedals) and the largest freewheel sprocket (attached to the rear wheel).

A. Your choice of gears doesn't matter because you'll do the same amount of work climbing the hill no matter which gear you choose.

A ball hits a wall going 10 m/s, and bounces off going 7 m/s. The coefficient of restitution is A. 1.41 B. 0.70 C. 0.49 D. -17 m/s

B. 0.70

You are swinging a tin can around your head in a perfectly horizontal circle of radius 4 m. (This is really not possible but we're saying it almost happens.) If the speed of the can is 4 m/s what is its acceleration? A. 1/4 m/s2 B. 4 m/s2 C. 16 m/s2 D. 4 m/s

B. 4 m/s2

The maximum speed a rocket can achieve is A. The speed of light B. Greater than the speed of its exhaust plume but less than the speed of light. C. Equal to the speed of its exhaust plume. D. The speed of sound E. Less than the speed of its exhaust plume.

B. Greater than the speed of its exhaust plume but less than the speed of light.

If a spring obeys Hooke's Law and you double the force with which you pull on it, A. Its length doubles. B. It stretches twice as far. C. It stretches four times as far. D. Its length increases by an amount that depends on what type of force you apply.

B. It stretches twice as far.

When an object is in unstable equilibrium,​ A. Any movement will decrease its potential energy. B. Some movements may decrease its potential energy. C. Some movements may increase its potential energy. D. Any movement will increase its potential energy.

B. Some movements may decrease its potential energy.

A motorcycle is A. Both statically and dynamically unstable B. Statically unstable and dynamically stable C. Statically stable and dynamically unstable D. Both statically and dynamically stable

B. Statically unstable and dynamically stable

Water settles to the bottom of a tank of gasoline. Which takes up more space: 1 kg of water or 1 kg of gasoline? A. 1 kg of gasoline because gasoline is more dense than water. B. 1 kg of water because water is more dense than gasoline. C. 1 kg of gasoline because gasoline is less dense than water. D. 1 kg of water because water is less dense than gasoline.

C. 1 kg of gasoline because gasoline is less dense than water.

The car is moving at 10 m/s relative to Bill. How fast does Amy see the car as moving? A. 5 m/s B. 10 m/s C. 15 m/s D. 20 m/s

C. 15 m/s

A popular playground toy is a flexible seat that has automobile springs attached to it for a little bounce. When a 200 N child sits on the toy, it compresses 5 mm downward. What is the ride's spring constant? A. 1000 N B. 5 mm C. 40000 N/m D. 1000 N/m

C. 40000 N/m

The coefficient of restitution for a particular ball is 0.45. If he ball hits a surface traveling at 100 m/s its rebound speed will be A. 100 m/s B. 90 m/s C. 45 m/s D. 45 m/s22610

C. 45 m/s

Your apparent weight is equal to your weight A. In an elevator accelerating upwards. B. In an elevator in free fall. C. In an elevator not accelerating. D. In an elevator accelerating downwards.

C. In an elevator not accelerating.

n a soccer game, someone has kicked the ball so that it is heading right toward your face. You want to slow the ball down with your arm. To execute your plan most effectively you should A. Move your arm rapidly toward the oncoming ball B. Keep your arm still C. Move your arm in the direction that the ball is moving D. Move your arm slowly toward the oncoming ball

C. Move your arm in the direction that the ball is moving

The coefficient of restitution is the ratio of: A. Rebound energy to collision energy. B. Collision energy to rebound energy. C. Rebound speed to collision speed. D. Collision speed to rebound speed.

C. Rebound speed to collision speed.

A "bouncy" or "lively" ball bounces higher from a rigid, immovable surface than a "dead" ball does because the "bouncy" ball A. Pushes harder on the surface B. Transfers less energy to the surface C. Returns more collision energy as rebound energy D. Obtains more rebound energy from the surface

C. Returns more collision energy as rebound energy

Each time you breathe in, air accelerates toward your nose and lungs. How does the pressure in your lungs compare with that in the surrounding air as you breathe in? A. The pressure in your lungs is greater than that of the surrounding air. B. There is no specific relationship between the pressure in your lungs and the pressure of the surrounding air. C. The pressure in your lungs is less than that of the surrounding air. D. The pressure in your lungs is equal to that of the surrounding air.

C. The pressure in your lungs is less than that of the surrounding air.

In what way does the string of a bow and arrow behave like a spring? A. It springs back when you pull on it. B. Actually, the string of a bow and arrow is nothing like a spring. C. The restoring force is proportional to the string's distortion.

C. The restoring force is proportional to the string's distortion.

It is important for cyclists to lean their bicycles while negotiating sharp turns because A. Their tires flatten out, thus getting better traction on the road. B. They increase their static stability C. The torque created by their leaning balances out the frictional torque from the road which would tend to flip them. D. The torque created by their leaning balances out their weight and holds them up.

C. The torque created by their leaning balances out the frictional torque from the road which would tend to flip them.

For an object that sinks in a fluid, A. The weight of the fluid displaced is greater than the object's weight. B. The weight of the fluid displaced equals the object's weight. C. The weight of fluid displaced is less than its weight. D. The weight of the object becomes more than in air.

C. The weight of fluid displaced is less than its weight.

For an object that is floating on a fluid, A. The weight of the fluid displaced is greater than the object's weight. B. The weight of the object becomes less than in air. C. The weight of the fluid displaced equals the object's weight. D. The weight of fluid displaced is less than its weight.

C. The weight of the fluid displaced equals the object's weight.

Astronauts in the space shuttle feel weightless because A. hey are moving very rapidly. B. They are so far away from the center of the Earth. C. They are in a constant state of free - fall. D. There is no atmosphere where they are.

C. They are in a constant state of free - fall.

You are riding an amusement park ride where you are strapped to the inside of a giant metal wheel that is rotating quite rapidly. Your acceleration is A. Zero B. Straight down C. Toward the center D. Straight up

C. Toward the center

When you are at stable equilibrium, A. Your potential energy is maximum. B. Your kinetic energy is minimum. C. Your potential energy is zero. D. Your potential energy is minimum.

D. Your potential energy is minimum.

If you pull down on the basket of a hanging grocery store scale so that it reads 15 N, how much downward force are you exerting on the basket? A. More information is needed. B. Greater than 15 N C. Less than 15 N D. 15 N

D. 15 N

What is the gravitational force that two 100 kg persons exert on each other when standing 1m apart? A. 6.672x10-11 N B. 10,000 N C, 1 N D. 6.672x10-7 N

D. 6.672x10-7 N

You are swinging a tin can around your head in a perfectly horizontal circle of radius 4 m. (This is really not possible but we're saying it almost happens.) If the speed of the can is 4 m/s and its mass is 2 kg, what inward force is required to keep the can moving in the circle? A. 1/16 N B. 2 N C. 16 N D. 8 N

D. 8 N

You are floating along in a hot air balloon. You look up and notice that the bottom of the balloon is open. Neglecting any diffusion of molecules, hot air remains inside the balloon despite this opening because A. Hot air has more inertia than cold air and doesn't accelerate easily. B. The propane burner located below the opening keeps pushing the hot air back into the balloon. C. Hot air has a lower pressure than cold air, so hot air is drawn into the balloon by the partial vacuum inside it. D. Convection naturally would make hot air rise, so it has no opening through which to escape.

D. Convection naturally would make hot air rise, so it has no opening through which to escape.

When you drop a rubber ball on the floor and it bounces, the direction of its velocity reverses because A. The ball can't stop moving and the floor blocks its path B. The ball's momentum is conserved C. The ball's energy is conserved D. The floor exerts an upward support force on the ball and this force stops the ball's descent and eventually propels it upward

D. The floor exerts an upward support force on the ball and this force stops the ball's descent and eventually propels it upward

Which object is exerting the stronger gravitational force on the other, the earth or the moon, or are the forces equal in magnitude? A. The force of the earth on the moon is stronger than the force of the moon on the earth. B. There is no specific relationship between the two forces. C. The force of the earth on the moon is weaker than the force of the moon on the earth. D. The force of the earth on the moon is equal to the force of the moon on the earth.

D. The force of the earth on the moon is equal to the force of the moon on the earth.

Why must tall dams be so much thicker at their bases than at their tops? A. The pressure is greater at the bottom due to greater kinetic energy per volume at the top. B. The pressure is greater at the bottom due to greater pressure at the top. C. A tall dam needs a lot of structural support. D. The greater the depth of the water the greater the pressure pushing on the wall of the dam.

D. The greater the depth of the water the greater the pressure pushing on the wall of the dam.

When a sharpshooter fires a pistol at a target, the gun recoils backward very suddenly, leaping away from the target. Explain this recoil effect in terms of the transfer of momentum. A. The gun's recoil is the reaction to the forward momentum of the bullet. B. The bullet transfers (backward) momentum to the gun. C. The gun transfers (forward) momentum to the bullet, so the gun recoils. D. The gun transfers (forward) momentum to the bullet, so the bullet transfers equal (backward) momentum to the gun.

D. The gun transfers (forward) momentum to the bullet, so the bullet transfers equal (backward) momentum to the gun.

Why is it so exhausting to run on soft sand? A. It takes more energy to run on sand. B. The sand has a low coefficient of restitution. C. The sand reduces the coefficient of restitution of your feet. D. The sand converts most of the energy of its collision with your feet into thermal energy instead of returning it to you.

D. The sand converts most of the energy of its collision with your feet into thermal energy instead of returning it to you.

As a skateboard rider performs stunts on the inside of a U-shaped surface, he often leans inward toward the middle of the U. Why does leaning keep him from falling over? A. The lean produces the torque which causes him to rotate as he moves along the U. B. The torque from the lean counteracts the torque from his center of gravity. C. The torque from his center of gravity causes him to rotate as he moves along the U. D. The support force from the surface of the U is at an angle, and leaning keeps his center of mass in line with the support force.

D. The support force from the surface of the U is at an angle, and leaning keeps his center of mass in line with the support force.

You are watching a semi truck bounce up and down on a spring. At the topmost point in the truck's path, A. the truck's velocity is downward but its acceleration is upward B. The truck's velocity is zero but its acceleration is upward C. The truck's velocity is upward but its acceleration is downward D. The truck's velocity is zero but its acceleration is downward.

D. The truck's velocity is zero but its acceleration is downward.

Some clear toys contain two colored liquids. No matter how you tilt one of those toys, one liquid remains above the other. What keeps the upper liquid above the lower liquid? A. The liquids can be mixed if you shake the toy vigorously. B. The upper liquid is filled with air. C. The upper liquid is more dense than the lower liquid. D. The upper liquid is less dense than the lower liquid.

D. The upper liquid is less dense than the lower liquid.