Physics Final

A 0.140-kg baseball is dropped and reaches a speed of 1.20 m/s just before it hits the ground and bounces. It rebounds with an upward velocity of 1.00 m/s. What is the change of the ball's momentum during the bounce? 0.0280 kg m/s upwards 0.0280 kg m/s downwards 0.308 kg m/s upwards 0.308 kg m/s downwards 0.000 kg m/s

.308 kg m/s upwards

A 0.140-kg baseball is dropped and reaches a speed of 1.20 m/s just before it hits the ground and bounces. It rebounds with an upward velocity of 1.00 m/s. What is the change of the ball's momentum during the bounce? 0.0280 kg m/s upwards 0.0280 kg m/s downwards 0.308 kg m/s upwards 0.308 kg m/s downwards 0.000 kg m/s

.308 kg upwards

By what length will a slab of concrete that is originally 18 m long contract when the temperature drops from 24°C to -16°C? The coefficient of linear thermal expansion for this concrete is 1.0 × 10-5 K-1. 0.50 cm 0.72 cm 1.2 cm 1.5 cm

.72 cm

Two ice skaters suddenly push off against one another starting from a stationary position. The 45-kg skater acquires a speed of 0.375 m/s relative to the ice. What speed does the 60-kg skater acquire relative to the ice? 0.50 m/s 0.28 m/s 0.38 m/s 0.75 m/s 0.00 m/s

0.28 m/s

Which two temperature changes are equivalent? 1 K = 1 F° 1 F° = 1 C° 1 C° = 1 K None of these

1 C = 1 K

A cable is 100-m long and has a cross-sectional area of 1.0 mm2. A 1000-N force is applied to stretch the cable. Young's modulus for the cable is 1.0 × 1011 N/m2. How far does the cable stretch? 0.010 m 0.10 m 1.0 m 10 m

1.0 m

A solid wood door, 90.0 cm wide by 2.00 m tall has a mass of 35.0 kg. It is open and at rest. A small 500-g ball is thrown perpendicular to the door with a speed of 20.0 m/s and hits the door 60.0 cm from the hinged side. The ball rebounds with a speed of 16.0 m/s along the same line. What is the angular speed of the door just after the collision with the ball? 0.127 rad/s 0.925 rad/s 1.14 rad/s 2.28 rad/s 4.57 rad/s

1.14 RADS

A solid wood door, 90.0 cm wide by 2.00 m tall has a mass of 35.0 kg. It is open and at rest. A small 500-g ball is thrown perpendicular to the door with a speed of 20.0 m/s and hits the door 60.0 cm from the hinged side. The ball rebounds with a speed of 16.0 m/s along the same line. What is the angular speed of the door just after the collision with the ball? 0.127 rad/s 0.925 rad/s 1.14 rad/s 2.28 rad/s 4.57 rad/s

1.14 rad/s

A hole in a brass plate has a diameter of 1.200 cm at 20°C. What is the diameter of the hole when the plate is heated to 220°C? The coefficient of linear thermal expansion for brass is 19 × 10-6 K-1. 1.205 cm 1.195 cm 1.200 cm 1.210 cm

1.205 cm

A 340-g air track cart traveling at 1.25 m/s suddenly collides elastically with a stationary 300-g cart. What is the speed of the 300-g cart just after the collision? 0.0781 m/s 1.33 m/s 0.625 m/s 1.25 m/s 0.664 m/s

1.33 m/s

A 340-g air track cart traveling at 1.25 m/s suddenly collides elastically with a stationary 300-g cart. What is the speed of the 300-g cart just after the collision? 0.0781 m/s 1.33 m/s 0.625 m/s 1.25 m/s 0.664 m/s

1.33 m/s

Fluid flows at 2.0 m/s through a pipe of diameter 3.0 cm. What is the volume flow rate of the fluid? 1.4 × 10-3 m3/s 5.7 × 10-3 m3/s 14 m3/s 57 m3/s

1.4 × 10-3 m3/s

A 12-L volume of oil is subjected to pressure which produces a volume strain of -3.0 × 10-4. The bulk modulus of the oil is 6.0 × 109 Pa and is independent of the pressure. The change in the pressure of the oil in megapascals is closest to 1.2 MPa. 1.4 MPa. 1.6 MPa. 1.8 MPa. 2.0 MPa.

1.8 MPa

A 12,000-N car is raised using a hydraulic lift, which consists of a U-tube with arms of unequal areas, filled with oil with a density of 800 kg/m3 and capped at both ends with tight-fitting pistons. The wider arm of the U-tube has a radius of 18.0 cm and the narrower arm has a radius of 5.00 cm. The car rests on the piston on the wider arm of the U-tube. The pistons are initially at the same level. What is the force that must be applied to the smaller piston in order to lift the car after it has been raised 1.20 m? For purposes of this problem, neglect the weight of the pistons. 0.954 kN 1.88 kN 1.96 kN 3.67 kN 1.20 kN

1.96 kN

A cubical box 25.0 cm on each side is immersed in a fluid. The pressure at the top surface of the box is 109.40 kPa and the pressure on the bottom surface is 112.00 kPa. What is the density of the fluid? 1000 kg/m3 1030 kg/ 1060 kg/m3 1090 kg/m3 1120 kg/m3

1060 kg/m3

Two vehicles approach a right angle intersection and then suddenly collide. After the collision, they become entangled. If their mass ratios were 1:4 and their respective speeds as they approached the intersection were both 13 m/s, find the magnitude and direction of the final velocity of the wreck. 11 m/s at 14° with respect to the original direction of the lighter car 16 m/s at 76° with respect to the original direction of the lighter car 11 m/s at 76° with respect to the original direction of the lighter car 26 m/s at 76° with respect to the original direction of the lighter car 16 m/s at 14° with respect to the original direction of the lighter car

11 m/s at 76° with respect to the original direction of the lighter car

A steel wire, 3.2 m long, has a diameter of 1.2 mm. The wire stretches 1.6 mm when it bears a load. Young's modulus for steel is 2.0 × 1011 Pa. The mass of the load is closest to 12 kg. 16 kg. 20 kg. 24 kg. 28 kg.

12 kg

At room temperature, a typical person loses energy to the surroundings at the rate of 62 W. If this energy loss has to be made up by an equivalent food intake, how many kilocalories (food calories) does this person need to consume every day just to make up this heat loss? (1 cal = 4.186 J) 1000 kcal 1100 kcal 1300 kcal 1500 kcal 1600 kcal

1300 kcal

A triatomic molecule is oriented as follows along the x-axis: mass m is at the origin, mass 2m is at x = a, and, mass 3m is at x = 2a. What is the moment of inertia of this molecule about the y-axis? 2ma2 3ma2 12ma2 14ma2

14 MA2

A 1500-kg car traveling at 90 km/h toward the east suddenly collides with a 3000-kg car traveling at 60 km/h toward the south. The two cars stick together after the collision. What is the speed of the cars after collision? 8.3 m/s 14 m/s 17 m/s 22 m/s

14 m/s

A bridge piling has a cross-sectional area of 1.250 m2 and supports a load of 1875 N. What is the stress on the column? 1875 N 1875 N/m2 1500 N/m2 2344 N/m2

1500 N/m2

An object having a fixed emissivity of 0.725 radiates heat at a rate of 10 W when it is at an absolute temperature T. If its temperature is doubled to 2T, at what rate will it now radiate? 20 W 40 W 80 W 160 W 320 W

160 w

A jogger is running outdoors on a cold day when the temperature is -20.0°C. She is breathing at the rate of 25 breaths per minute, and each time she breathes in she inhales 0.00450 m3 of air. How much heat does she lose from breathing during 20.0 minutes of jogging if the air in her lungs is heated to her body temperature of 37.0°C before it is exhaled? The specific heat of air is 1020 J/kg K and the density of air under typical conditions is 1.29 kg/m3. 169 kJ 278 kJ 354 kJ 431 kJ 543 kJ

169 kj

How many grams of ethanol (density 0.80 g/cm3) should be added to 5.0 g of chloroform (density 1.5 g/cm3) if the resulting mixture is to have a density of 1.2 g/cm3? Assume that the fluids do not change their volumes when they are mixed. 2.0 g 2.4 g 1.8 g 4.4 g 1.6 g

2.0 g

A uniform 40-N board supports two children weighing 500 N and 350 N. If the support is at the center of the board and the 500-N child is 1.5 m from its center, how far is the 350-N child from the center? 1.1 m 1.5 m 2.1 m 2.7 m

2.1 m

A 25-kg television set rests on four rubber pads that are on the floor, each one having a height of 1.0 cm and a radius of 0.60 cm. A horizontal force is applied to the television set. When the pads are just at the point of sliding over the floor, how far has the television set moved sideways due to the deformation of the pads? The coefficient of static friction between the rubber and the floor is 1.0 and the shear modulus of these rubber pads is 2.6 × 106 Pa. 16 mm 8.4 mm 4.2 mm 2.1 mm 1.1 mm

2.1 mm

In a hydraulic garage lift, the small piston has a radius of 5.0 cm and the large piston has a radius of 15 cm. What force must be applied on the small piston in order to lift a car weighing 20,000 N on the large piston? Assume the pistons each have negligible weight. 6.7 × 103 N 5.0 × 103 N 2.9 × 103 N 2.2 × 103 N

2.2 × 103 N

Ideal incompressible water is flowing in a drainage channel of rectangular cross-section. At one point, the width of the channel is 12 m, the depth of water is 6.0 m, and the speed of the flow is 2.5 m/s. At a point downstream, the width has narrowed to 9.0 m, and the depth of water is 8.0 m. What is the speed of the flow at the second point? 2.0 m/s 2.5 m/s 3.0 m/s 3.5 m/s 4.0 m/s

2.5 m/s

Two identical objects are placed in a room with a temperature of 20°C. Object A has a temperature of 50°C, while object B has a temperature of 90°C. What is the ratio of the net power emitted by object B to the power emitted by object A? 1.7 2.8 81 17 21

2.8

How much heat must be removed from 456 g of water at 25.0°C to change it into ice at -10.0°C? The specific heat of ice is 2090 J/kg K, the latent heat of fusion of water is 33.5 × 104 J/kg, and the specific heat of water is 4186 J/kg K. 105 kJ 153 kJ 57.3 kJ 47.7 kJ 210 kJ

210 kj

Two dogs, Rover and Fido, run on a level frictionless surface. Rover runs eastward with a momentum of 24 kg . m/s, and Fido runs northward with momentum 10 kg . m/s. They make a sudden perfectly inelastic collision. What is the magnitude of their combined momentum after the collision? 14 kg . m/s 26 kg . m/s 34 kg . m/s It cannot be determined without knowing the masses and velocities of the dogs.

26 KG

An ideal gas is held in a container of volume V at pressure p. The rms speed of a gas molecule under these conditions is v. If now the volume and pressure are changed to 2V and 2p, the rms speed of a molecule will be v/2 v 2v 4v v/4

2v

An aluminum wire 2.0 m long and 2.0 mm in diameter supports a 10.0-kg fixture. What is the stress in the wire? Young's modulus for aluminum is 7.0 × 1010 N/m2. 3.1 × 107 N/m2 6.2 × 107 N/m2 9.3 × 107 N/m2 1.2 × 108 N/m2

3.1 × 107 N/m2

A 50-kg load is suspended from a steel wire of diameter 1.0 mm and length 11.2 m. By what distance will the wire stretch? Young's modulus for steel is 2.0 × 1011 Pa. 1.5 cm 2.5 cm 3.5 cm 4.5 cm

3.5 cm

A 50-kg load is suspended from a steel wire of diameter 1.0 mm and length 11.2 m. By what distance will the wire stretch? Young's modulus for steel is 2.0 × 1011 Pa. 1.5 cm 2.5 cm 3.5 cm 4.5 cm

3.5 cm

A solid uniform disk of diameter 3.20 m and mass 42 kg rolls without slipping to the bottom of a hill, starting from rest. If the angular speed of the disk is 4.27 rad/s at the bottom, how high did it start on the hill? 3.57 m 2.68 m 3.14 m 4.28 m

3.57 M

Under standard conditions, the density of air is 1.29 kg/m3. What is the mass of the air inside a room measuring 4.0 m × 3.0 m × 2.0 m? 0.32 kg 3.1 kg 31 kg 1.9 kg 19 kg

31 kg

A person tries to heat up her bath water by adding 5.0 L of water at 80°C to 60 L of water at 30°C. What is the final temperature of the bath water? 34°C 36°C 38°C 40°C

34

A 4.0-kg cylinder of solid iron is supported by a string while submerged in water. What is the tension in the string? The density of iron is 7860 kg/m3 and that of water is 1000 kg/m3. 2.5 N 20 N 24 N 34 N 40 N

34 N

Two uniform solid spheres have the same mass, but one has twice the radius of the other. The ratio of the larger sphere's moment of inertia about a central axis to that of the smaller sphere is 4/5. 8/5. 1/2. 2. 4.

4

Ideal incompressible fluid flows through a 4.0-cm-diameter pipe at 1.0 m/s. There is a 2.0 cm diameter constriction in the line. What is the speed of the fluid in this constriction? 0.25 m/s 0.50 m/s 2.0 m/s 4.0 m/s

4.0

A uniform solid disk is released from rest and rolls without slipping down an inclined plane that makes an angle of 25° with the horizontal. What is the forward speed of the disk after it has rolled 3.0 m, measured along the plane? 2.0 m/s 3.5 m/s 4.1 m/s 5.7 m/s 6.3 m/s

4.1 m/s

A hoop is rolling without slipping along a horizontal surface with a forward speed of 5.50 m/s when it starts up a ramp that makes an angle of 25.0° with the horizontal. What is the speed of the hoop after it has rolled 3.00 m up as measured along the surface of the ramp? 4.22 m/s 1.91 m/s 2.06 m/s 3.79 m/s 8.02 m/s

4.22 M/S

A quantity of mercury occupies 400.0 cm3 at 0°C. What volume will it occupy when heated to 50°C? Mercury has a volume expansion coefficient of 180 × 10-6 K-1. 450 cm3 409.7 cm3 403.6 cm3 401.8 cm3

403.6

A sealed cylinder fitted with a movable piston contains ideal gas at 27°C, pressure 0.500 × 105 Pa, and volume 1.25 m3. What will be the final temperature if the gas is compressed to 0.800 m3 and the pressure rises to 0.820 × 105 Pa? 42°C 68°C 130°C 250°C 150°C

42

A hoop with a mass of 2.75 kg is rolling without slipping along a horizontal surface with a speed of 4.5 m/s when it starts down a ramp that makes an angle of 25° below the horizontal. What is the rotational kinetic energy of the hoop after it has rolled 3.0 m down as measured along the surface of the ramp? 34 J 22 J 45 J 62 J

45 J

A hole of radius 1.0 mm forms in the bottom of a very large water storage tank that holds water to a depth of 15 m. At what volume rate will water flow out of the hole? 5.4 × 10-4 m3/s 5.4 × 10-5 m3/s 5.4 × 10-6 m3/s 5.4 × 10-7 m3/s

5.4 × 10-5 m3/s

The coefficient of linear expansion for aluminum is 1.8 × 10-6 K-1. What is its coefficient of volume expansion? 9.0 × 10-6 K-1 5.8 × 10-18 K-1 5.4 × 10-6 K-1 3.6 × 10-6 K-1 0.60 × 10-6 K-1

5.4 × 10-6 K-1

A vertical 30-cm steel rod, 1.0 cm in diameter, supports a 300-kg mass. What is the change in length of the rod caused by this mass? Young's modulus for steel is 2.0 × 1011 N/m2. 5.6 × 10-5 m 6.5 × 10-5 m 5.6 × 10-6 m 6.5 × 10-6 m 6.5 × 10-4 m

5.6 × 10-5 m

A solid cylindrical bar conducts heat at a rate of 25 W from a hot to a cold reservoir under steady state conditions. If both the length and the diameter of this bar are doubled, the rate at which it will conduct heat between these reservoirs will be 200 W 100 W 50 W 25 W 12.5 W

50 w

A runner generates 1260 W of thermal energy. If this heat has to be removed only by evaporation, how much water does this runner lose in 15 minutes of running? The latent heat of vaporization of water is 22.6 × 105 J/kg. 50 g 500 g 35 g 350 g 40 g

500 g

A car starts out when the air temperature is 288 K and the absolute (total) air pressure in the tires is 500 kPa. After driving a while, the temperature of the air in the tires increases to 298 K. What is the pressure in the tires at that point, assuming their volume does not change? 129 kPa 483 kPa 507 kPa 517 kPa 532 kPa

517 KpA

A 4.0-kg aluminum block is originally at 10°C. If 160 kJ of heat is added to the block, what is its final temperature? The specific heat capacity of aluminum is 910 J/kg K. 24°C 34°C 44°C 54°C

54

A sealed container holds 0.020 moles of ideal nitrogen (N2) gas, at a pressure of 1.5 atm and a temperature of 290 K. The atomic mass of nitrogen is 14.0 g/mol. What is the average translational kinetic energy of a nitrogen molecule? The Boltzmann constant is 1.38 × 10-23 J/K. 4.0 ×1021 J 6.0 ×1021 J 8.0 ×1021 J 10 ×1021 J 12 ×1021 J

6.0 ×1021 J

The coefficient of linear expansion of copper is 17 × 10-6 K-1. A block of copper 30 cm wide, 45 cm long, and 10 cm thick is heated from 0°C to 100°C What is the change in the volume of the block? 2.3 × 10-5 m3 4.6 × 10-5 m3 5.2 × 10-5 m3 6.9 × 10-5 m3 14 × 10-5 m3

6.9 × 10-5 m3

A refrigerator has an interior volume of 0.500 m3. The temperature inside the refrigerator in 282 K, and the pressure is 101 kPa. If the molecular weight of air is 29 g/mol, what is the mass of air inside the refrigerator? (R = 8.31 J/mol × K) 625 g 513 g 447 g 329 g 243 g

625 g

A camper is about to drink his morning coffee. He pours 400 grams of coffee, initially at 75°C into a 250-g aluminum cup, initially at 16°C. What is the equilibrium temperature of the coffee-cup system, assuming no heat is lost to the surroundings? The specific heat of aluminum is 900 J/kg K, and the specific heat of coffee is essentially the same as that of water, which is 4186 J/kg K. 45°C 62°C 65°C 68°C 71°C

68

Suppose that a rigid aluminum wire were to be strung out in a loop that just fits snugly around the equator (assuming a perfectly spherical Earth with a radius of 6.37 × 106 m). If the temperature of the wire is increased by 0.50°C, and the increase in length is distributed equally over the entire length, how far off the ground will the wire loop be if it remained centered on the earth? The coefficient of linear expansion of aluminum is 24 × 10-6 K-1. 7.6 mm 76 mm 76 cm 76 m 760 m

76 M

To drive a typical car at 40 mph on a level road for one hour requires about 3.2 × 107 J of energy. Suppose we tried to store this much energy in a spinning, solid, uniform, cylindrical flywheel. A large flywheel cannot be spun too fast or it will fracture. If we used a flywheel of diameter 1.2 m and mass 400 kg, what angular speed would be required to store 3.2 × 107 J? 1800 rad/s 3600 rad/s 940 rad/s 530 rad/s 5500 rad/s

940 rads

A scooter has wheels with a diameter of 120 mm. What is the angular speed of the wheels when the scooter is moving forward at 6.00 m/s? 47.7 rpm 955 rpm 72.0 rpm 50.0 rpm 100 rpm

955 rpm

Two children, Ahmed and Jacques, ride on a merry-go-round. Ahmed is at a greater distance from the axis of rotation than Jacques. Which of the following are true statements? (There could be more than one correct choice.) Jacques has a greater angular speed than Ahmed. Jacques and Ahmed have the same angular speed. Jacques has a smaller angular speed than Ahmed. Ahmed has a greater tangential speed than Jacques. Jacques and Ahmed have the same tangential speed.

Ahmed has a greater tangential speed than Jacques Jacques and Ahmed have the same angular speed

If the sum of the external forces on an object is zero, then the sum of the external torques on it must also be zero. True False

False

If the sum of the external torques on an object is zero, then the sum of the external forces on it must also be zero. You Answered True False

False

Which one of the following would be expected to have the smallest bulk modulus? liquid mercury liquid water helium vapor solid iron solid uranium

Helium Vapor

A spinning ice skater on extremely smooth ice is able to control the rate at which she rotates by pulling in her arms. Which of the following statements are true about the skater during this process? (There could be more than one correct choice.) Her angular momentum remains constant. Her moment of inertia remains constant. Her kinetic energy remains constant. She is subject to a constant non-zero torque.

Her angular momentum remains constant

A piece of wood is floating in a bathtub. A second piece of wood sits on top of the first piece, and does not touch the water. If the top piece is taken off and placed in the water, what happens to the water level in the tub? It goes up. It goes down. It does not change. It cannot be determined without knowing the volumes of the two pieces of wood.

It does not change

The coefficient of linear expansion of copper is 17 × 10-6 K-1. A sheet of copper has a round hole with a radius of 3.0 m cut out of it. If the sheet is heated and undergoes a change in temperature of 80 K, what is the change in the radius of the hole? It decreases by 4.1 mm. It increases by 4.1 mm. It decreases by 8.2 mm. It increases by 8.2 mm. It does not change.

It increases by 4.1 mm.

The water pressure to an apartment is increased by the water company. The water enters the apartment through an entrance valve at the front of the apartment. Where will the increase in the static water pressure be greatest when no water is flowing in the system? at a faucet close to the entrance valve at a faucet far from the entrance valve It will be the same at all faucets. There will be no increase in the pressure at the faucets.

It will be the same at all faucets

Two blocks are made of the same material, but one has twice the volume of the other block. Which block will have the greater shear modulus? It will be the same for both of them. the larger one the smaller one

It will be the same for both of them

Two solid spheres are made from the same material, but one has twice the diameter of the other. Which sphere will have the greater bulk modulus? the larger one the smaller one It will be the same for both spheres.

It will be the same for both spheres

Two wires are made out of the same metal, but one wire is twice as long as the other wire. Which wire will have the greatest elastic modulus? the shorter wire the longer wire It will be the same for both wires.

It will be the same for both wires

Two children, Ahmed and Jacques, ride on a merry-go-round. Ahmed is at a greater distance from the axis of rotation than Jacques. Which of the following are true statements? (There could be more than one correct choice.) Jacques has a greater angular speed than Ahmed. Jacques and Ahmed have the same angular speed. Jacques has a smaller angular speed than Ahmed. Ahmed has a greater tangential speed than Jacques. Jacques and Ahmed have the same tangential speed.

Jacques and Ahmed have the same angular speed. Ahmed has a greater tangential speed than Jacques.

If a quantity you calculated had units of kg m/s, what type of quantity could it be? (There could be more than one correct choice.) momentum kinetic energy work impulse force

Momentum Impulse

A thermally isolated system is made up of a hot piece of aluminum and a cold piece of copper, with the aluminum and the copper in thermal contact. The specific heat capacity of aluminum is more than double that of copper. Which object experiences the greater magnitude gain or loss of heat during the time the system takes to reach thermal equilibrium? the aluminum the copper Neither one; both of them experience the same size gain or loss of heat. It is impossible to tell without knowing the masses. It is impossible to tell without knowing the volumes.

Neither one; both of them experience the same size gain or loss of heat.

A solid sphere, solid cylinder, and a hollow pipe all have equal masses and radii. If the three of them are released simultaneously at the top of an inclined plane and do not slip, which one will reach the bottom first? sphere pipe cylinder The pipe and cylinder arrive together before the sphere. They all reach the bottom at the same time.

SPHERE

Two friends are standing on opposite ends of a canoe that is initially at rest with respect to a frictionless lake. The person in the front throws a very massive ball toward the back, and the person in the back catches it. After the ball is caught, the canoe is moving backward. stationary. moving forward.

Stationary

A rubber ball and a lump of clay have equal mass. They are thrown with equal speed against a wall. The ball bounces back with nearly the same speed with which it hit. The clay sticks to the wall. Which one of these objects experiences the greater momentum change? the ball the clay Both of them experience the same non-zero momentum change. Both of them experience zero momentum change.

The ball

As a rock sinks deeper and deeper into water of constant density, what happens to the buoyant force on it if it started above the surface of the water? The buoyant force keeps increasing steadily. The buoyant force remains constant. The buoyant force first increases and then remains constant. The buoyant force steadily decreases.

The buoyant force first increases and then remains constant.

Salt water has greater density than fresh water. A boat floats in both fresh water and in salt water. Where is the buoyant force greater on the boat? in salt water in fresh water The buoyant force is the same in both cases.

The buoyant force is the same in both cases.

Consider two less-than-desirable options. In the first you are driving 30 mph and crash head-on into an identical car also going 30 mph. In the second option you are driving 30 mph and crash head-on into a stationary brick wall. In neither case does your car bounce back from the thing it hits, and the collision time is the same in both cases. Which of these two situations would result in the greater impact force on your car? hitting the other car hitting the brick wall The force would be the same in both cases. None of these choices are correct.

The force would be the same in both cases

A fixed container holds oxygen and helium gases at the same temperature. Which of the following statements are correct? (There could be more than one correct choice.) The oxygen molecules have the greater average kinetic energy. The helium molecules have the greater average kinetic energy. The oxygen molecules have the greater speed. The helium molecules have the greater speed. The helium molecules have the same average kinetic as the oxygen molecules.

The helium molecules have the greater speed. The helium molecules have the same average kinetic as the oxygen molecules.

A rocket explodes into two fragments, one 25 times heavier than the other. The magnitude of the momentum change of the lighter fragment is 25 times as great as the momentum change of the heavier fragment. The same as the momentum change of the heavier fragment. 1/25 as great as the momentum change of the heavier fragment. 5 times as great as the momentum change of the heavier fragment. 1/4 as great as the momentum change of the heavier fragment.

The same momentum change of the heavier fragment

A small car meshes with a large truck in a head-on collision. Which of the following statements concerning the magnitude of the average force during the collision is correct? A) The truck experiences the greater average force. B) The small car experiences the greater average force. C)The small car and the truck experience the same average force. D) The force experienced by each one is inversely proportional to its mass. E) The force experienced by each one is directly proportional to its mass.

The small car and truck experience the same average force

Three cars, car X, car Y, and car Z, begin accelerating from rest at the same time. Car X is more massive than car Y, which is more massive than car Z. The net accelerating force exerted on each car is identical. After 10 seconds, which car has the most amount of momentum? They all have the same amount of momentum. Car X Car Y Car Z

They all have the same amount of momentum

Three small masses are positioned at the following coordinates: 3.0 kg at (3.0 m, 2.0 m); 4.0 kg at (0.0 m, -1.0 m); and 5.0 kg at (5.0 m, -7.0 m). What are the coordinates of the center of mass (or center of gravity) of this system? Fill in the blank

WORK THIS OUT, FIGURE IT OUT

Tensile stress is the strain per unit length. the same as force. the ratio of the change in length. applied force per cross-sectional area.

applied force per cross-sectional area.

Oxygen molecules are 16 times more massive than hydrogen molecules. At a given temperature, how do their average molecular speeds compare? The oxygen molecules are moving four times faster than the hydrogen molecules. at 1/4 the speed of the hydrogen molecules. sixteen times faster than the hydrogen molecules. at 1/16 the speed of the hydrogen molecules.

at 1/4 the speed of the hydrogen molecules.

The process in which heat flows by the mass movement of molecules from one place to another is known as conduction. convection. radiation.

convection

A disk and a hoop of the same mass and radius are released at the same time at the top of an inclined plane. If both are uniform, which one reaches the bottom of the incline first if there is no slipping? The hoop The disk Both reach the bottom at the same time.

disk

As you are leaving a building, the door opens outward. If the hinges on the door are on your right, what is the direction of the angular velocity of the door as you open it? up down to your left to your right forwards

down

A ballet dancer is spinning in the middle of a horizontal frictionless stage. Which of the following things could he change by moving parts of his body or his whole body? (There could be more than one correct choice.) his total kinetic energy his translational kinetic energy his rotational kinetic energy his angular momentum his moment of inertia the horizontal component of his linear momentum the location of his center of mass (or center of gravity)

his total kinetic energy his translational kinetic energy his rotational kinetic energy his angular momentum his moment of inertia the location of his center of mass (or center of gravity)

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 increase by a factor of 3. increase by a factor of 9. increase by a factor of 18. increase by a factor of 27. increase by a factor of 81.

increase by a factor of 81

An air bubble underwater has the same pressure as that of the surrounding water. As the air bubble rises toward the surface (and its temperature remains constant), the volume of the air bubble increases. decreases. remains constant. increases or decreases, depending on the rate it rises.

increases

Oxygen molecules are 16 times more massive than hydrogen molecules. At a given temperature, the average molecular kinetic energy of oxygen molecules, compared to that of hydrogen molecules, is greater. is less. is the same. cannot be determined without knowing the pressure and volume.

is the same

A piece of wood is floating in a bathtub. A second piece of wood sits on top of the first piece, and does not touch the water. If the top piece is taken off and placed in the water, what happens to the water level in the tub? It goes up. It goes down. It does not change. It cannot be determined without knowing the volumes of the two pieces of wood.

it does not change

A thermally isolated system is made up of a hot piece of aluminum and a cold piece of copper, with the aluminum and the copper in thermal contact. The specific heat capacity of aluminum is more than double that of copper. Which object experiences the greater temperature change during the time the system takes to reach thermal equilibrium? the copper the aluminum Neither one; both of them experience the same size temperature change. It is impossible to tell without knowing the masses. It is impossible to tell without knowing the volumes.

it is impossible to tell without knowing the masses

Which one of the following quantities is the smallest unit of heat energy? calorie kilocalorie Btu joule

joule

An egg falls from a bird's nest in a tree and feels no effects due to the air. As it falls, only its kinetic energy is conserved. only its momentum is conserved. both its kinetic energy and its momentum are conserved. only its mechanical energy is conserved. both its mechanical energy and its momentum are conserved

only mechanical energy is conserved

A wooden block contains some nails so that its density is exactly equal to that of water. If it is placed in a tank of water and released from rest when it is completely submerged, it will rise to the surface. sink to the bottom. remain where it is released.

remain where it is released

If you wanted to know how much the temperature of a particular piece of material would rise when a known amount of heat was added to it, which of the following quantities would be most helpful to know? initial temperature specific heat density coefficient of linear expansion thermal conductivity

specific heat

A solid sphere, solid cylinder, and a hollow pipe all have equal masses and radii. If the three of them are released simultaneously at the top of an inclined plane and do not slip, which one will reach the bottom first? sphere pipe cylinder The pipe and cylinder arrive together before the sphere. They all reach the bottom at the same time.

sphere

When you blow some air above a paper strip, the paper rises. This happens because the air above the paper moves faster and the pressure is higher. the air above the paper moves faster and the pressure is lower. the air above the paper moves faster and the pressure remains constant. the air above the paper moves slower and the pressure is higher. the air above the paper moves slower and the pressure is lower.

the air above the paper moves faster and the pressure is lower.

The absolute temperature of an ideal gas is directly proportional to which of the following quantities? the average speed of its molecules the average momentum of its molecules the average kinetic energy of its molecules the mass of its molecules It is proportional to all of these quantities.

the average kinetic energy of its molecules

A rubber ball and a lump of clay have equal mass. They are thrown with equal speed against a wall. The ball bounces back with nearly the same speed with which it hit. The clay sticks to the wall. Which one of these objects experiences the greater momentum change? the ball the clay Both of them experience the same non-zero momentum change. Both of them experience zero momentum change.

the ball

A waiter fills your water glass with ice water (containing many ice cubes) such that the liquid water is perfectly level with the rim of the glass. As the ice melts, the liquid-water level remains flush with the rim of the glass. the liquid water level rises, causing water to run down the outside of the glass. the liquid-water level decreases.

the liquid-water level remains flush with the rim of the glass.

Suppose a solid uniform sphere of mass M and radius R rolls without slipping down an inclined plane starting from rest. The angular velocity of the sphere at the bottom of the incline depends on the mass of the sphere. the radius of the sphere. both the mass and the radius of the sphere. neither the mass nor the radius of the sphere.

the radius of the sphere.

Which one of the following is an accurate statement? The ratio of tensile stress to tensile strain is called Young's modulus. "Strain" has a meaning very close to "force." "Stress" has a meaning very close to "stretch." Tensile stress is measured in newtons. Tensile strain is measured in meters.

the ratio of tensile stress to tensile strain is called Young's modulus

A small uniform disk and a small uniform sphere are released simultaneously at the top of a high inclined plane, and they roll down without slipping. Which one will reach the bottom first? the one of smallest diameter the one of greatest mass the disk the sphere They will reach the bottom at the same time.

the sphere

When a car is weighed, it is driven slowly on a horizontal floor over a scale that records a reading as the front wheels go over the scale, and then records a second reading as the rear wheels go over the scale. The weight of the car is equal to the weight under the front wheels. the weight under the rear wheels. the average of the two weights. the sum of the two weights. the difference of the two weights.

the sum of the two weights

Two metal spheres are made of the same material and have the same diameter, but one is solid and the other is hollow. If their temperature is increased by the same amount, the solid sphere becomes bigger than the hollow one. the hollow sphere becomes bigger than the solid one. the two spheres remain of equal size. the solid sphere becomes denser and the hollow one less dense.

the two spheres remain of equal size

If the answer to your calculation has units of kg m2/s2 , what type of quantity could it be? (There could be more than one correct choice.) force work angular momentum linear momentum power rotational kinetic energy moment of inertia torque

work rotational kinetic energy torque