physics 1310--- Test 2

Density

" how compact the matter is "

velocity changes and acceleration occurs

if momentum changes but the mass stays the same what else is occurring?

C. Archimedes principal

How a ship floats is described in terms of a) Pascal's principle b) Bernouilli's principle c) Archimede's principle d) Poiseuille's principle

C Archimede's Principle

How a ship floats is described in terms of a)Pascal's principle b) Bernouilli's principle c) Archimede's principle d) Poiseuille's principle

25 J

How much kinetic energy does a 20 N block have when moving at 5 m/s?

b) momentum

impulse changes ___________ a) inertia b) momentum c) force d) acceleration

A. 1Kg AL same mass more dense material --> smaller volume

Lead is more dense than Aluminum which has a larger volume? a) 1Kg AL b) 1Kg Lead c) same

A. 1N AL weight =MG

Lead is more dense than Aluminum which has a larger volume? a) 1N AL b) 1N Lead c) same

8.96 g/cm^3

A 10.0 cm3 sample of copper has a mass of 89.6 g. The density of this sample is ________g/cm^3.

P=MV 3 m/s

A 4 kg object has a momentum of 12 kg•m/s. The object's speed is ___ m/s

B. the iron

A 50-cm3 block of wood is floating partially submerged in water, and a 50-cm3 block of iron is totally submerged in water. Which block has the greater buoyant force on it? a) the wood b) the iron c) same

B. the iron

A 50-cm3 block of wood is floating partially submerged in water, and a 50-cm3 block of iron is totally submerged in water. Which block has the greater buoyant force on it? a) the wood b) the iron c) same

A. less than 100J

A ball is projected into the air with 100 J of kinetic energy. The kinetic energy is transformed into gravitational potential energy on the path towards the peak of its trajectory. When the ball returns to its original height, its kinetic energy is ____ Joules. Do consider the effects of air resistance a) less than 100 b) 100 c) more than 100

c) they are the same

A compact car and a large truck have a head on collision. what undergoes the bigger change in momentum? a) the car b) the large truck c) they are the same d) not enough info

B. doubles

A doubling in velocity ________ the momentum a) quadruple b) double c) triple d) stays the same

A. 12P

A force produces power P by doing work W in a time T. What power will be produced by a force that does six times as much work in half as much time? a) 12P b) 6P c) 1/6P d) 1/12P

A. just as they leave the ground, the lighter front is moving faster than the heavier frog B. Both frogs reach the same maximum height

A heavy frog and a light frog jump straight up into the air. They push off in such away that they both have the same kinetic energy just as they leave the ground. Air resistance is negligible. Which of the following statements about these frogs are correct? (There could be more than one correct choice.) a) Just as they leave the ground, the lighter frog is moving faster than the heavier frog. b) Both frogs reach the same maximum height. c) The lighter frog goes higher than the heavier frog. d) Just as they leave the ground, the heavier frog is moving faster than the lighter frog. e) The heavier frog goes higher than the lighter frog. f) They both leave the ground with the same speed.

10,000 Kg P=M/V

A metal block has a density of 5000 kg per cubic meter and a volume of 2 cubic meters. What is the block's mass?

C. 5000J

A platform diver weighs 500 N. She steps off a diving board that is elevated to a height of 10 meters above the water. The diver will possess ___ Joules of kinetic energy when she hits the water. a) 500J b) 50J C) 5000J d) 100J

A. Ring

A ring and a disk (with same mass) both at rest roll down a hill together. Which rolls slower? A) ring b) disk c) same

2N

A rock suspended by a string weighs 5 N out of water and 3 N when submerged. What is the buoyant force on the rock?

D. her angular momentum remains constant

A spinning ice skater is able to control the rate at which she rotates by pulling in her arms. We can best understand this effect by observing that in this process: a) her kinetic energy remains constant. b) her moment of inertia remains constant. c) she is subject to a constant non-zero torque. d) her angular momentum remains constant. d) her total velocity remains constant.

C. Doubles

A truck has a large momentum. If the truck moves at a constant speed but has twice as much mass, its momentum is.. a) tripled b) stays the same c) doubled d) quadruples

B. increases

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 a) remains constant b) increases c) decreases

B. 50J

An arrow is drawn back so that 50 Joules of potential energy is stored in the stretched bow and string. When released, the arrow will have a kinetic energy of ____ Joules. a) 100J b) 50J c) 75J d) 30J

A. volume

As a balloon high in the atmosphere descends, it undergoes a decrease in a) volume b) weight c) mass d) density

D. density

As a high-altitude balloon rises higher into the atmosphere, it undergoes a decrease in a) weight b) volume c) mass d) density

C. 1 Kg block of aluminum

Buoyant force is greatest on a submerged a) same b) 1kg block of lead c) 1 kg block of aluminum

B. the same

Compared to a bar of pure gold, the density of a pure gold ring is a) less b) the same c) more

B. temperature

Density depends on ______ a) height b) temperature c) volume d) inertia

540 kg/m/s eastward P=MV 60*9= 540

Determine the momentum: 60 Kg halfback moving eastward at 9 m/s

B. no, because the force and the displacement of the object are perpendicular

Does the centripetal force acting on an object do work on the object? a) no, because the object has constant speed b) no, because the force and the displacement of the object are perpendicular c) yes, because the force and the displacement of the object are perpendicular d)yes, since it takes energy to turn an object

C. be acted on by a continuously decreasing buoyant force

If a weighted air-filled balloon sinks in deep water, it will a) likely burst if water pressure is great enough. b) likely sink to an equilibrium level before reaching bottom. c) be acted on by a continuously decreasing buoyant force. d) one of the above

B. Lead

If the density of mercury is 13.6 g/mL and the density of lead is 11.3 g/mL, which has the larger volume: 1 g of mercury or 1 g of lead? a) mercury b) lead c) both have the same volume

C. Double

If the mass of an object were to double while its volume remains the same, its density would a) become four times as great. b) stay the same. c) double. d) halve.

A. triple

If the mass of an object were to triple while its volume remains the same, its density would a) triple b) decrease by 1/3 c) stay the same

D. four times jacks power output

Jill does twice as much work as Jack does and in half the time. Jill's power output is a) one-half as much as Jack's power output. b) the same as Jack's power output. c) twice Jack's power output. d) four times Jack's power output.

B. 1cm^2 Lead same volume-- more dense-- more mass-- will need more particles

Lead is more dense than Aluminum which has a larger mass? a) 1cm^3 AL b) 1cm^2 Lead c) same

A. 34.9 mL

Mercury has a density of 13.6 g/mL. How many milliliters of mercury have a mass of 475 g? a) 34.9 mL b) 0.000155 mL c) 0.0286 mL d) 6460 mL

Circular Motion

Motion of objects which either move in circles or can be approximated to be moving in circles

Potential energy ex: A stretched bow has stored energy that can do work on an arrow. ex: A stretched rubber band of a slingshot has stored energy and is capable of doing work.

Stored energy held in readiness with a potential for doing work

B) Both take the same time

Suppose a ping-pong ball and a bowling ball are rolling toward you. Both have the same momentum, and you exert the same force to stop each. How do the time intervals to stop them compare? a) It takes less time to stop the ping-pong ball. b) Both take the same time. c) It takes more time to stop the ping-pong ball.

TRUE

T/F Archimedes' principal was volume of an object submerged is equal to the volume of the fluid displaced.

TRUE Impulse changes Momentum formula form: Ft=(changing) MV

T/F The greater the impulse exerted on something, the greater the change in momentum.

TRUE

T/F if you do the same work in shorter time you generate more power

TRUE

T/F the more momentum an object has the harder it is to stop

TRUE

T/F when the speed of fluid increases-- the internal pressure of the fluid decreases

FALSE whenever you find acceleration you will find force

T/F whenever you find acceleration you will not find force

TRUE

T/F A bowling ball is mounted from a ceiling by way of a strong cable. It is drawn back and released, allowed to swing as a pendulum. As it swings from its highest position to its lowest position, the total mechanical energy is mostly conserved.

TRUE

T/F As you increase your rotational speed, you increase your tangential speed

TRUE

T/F center of gravity is average position of weight distribution

True

T/F heat is transferred from a high temp to a low temp

TRUE

T/F the center of mass is the point where all of the mass of the object is concentrated

TRUE

T/F A doubling of mass doubles the momentum

FALSE

T/F The buoyant force acting on an object is equal to the weight of the object.

FALSE. a LARGER time requires a SMALLER force for the same change in momentum.

T/F a smaller time requires a larger force for the same change in momentum.

FALSE the further you move out from the middle, the FASTER your speed

T/F the further you move out from the middle, you move at a slower speed

centripetal acceleration

The acceleration of a body experiencing uniform circular motion is always directed toward the center of the circle, so we call that acceleration

B. weight of air displaced

The buoyant force of the atmosphere on a body is equal to the a) volume of air displaced. b) weight of air displaced. c) mass of the air displaced. d) all of the above

C. one ton

The buoyant force on a one-ton blimp hovering in air is a) zero b) less than one ton c) one ton d) more than one ton

A. partly submerged

The buoyant force on an object is least when the object is a) partly submerged b) submerged near the bottom c) submerged near the surface d) none of these

2 m/s

The circumference of a bicycle wheel is 2 meters. If it rotates at 1 revolution per second then its linear speed is ______ m/s.

D. Archimedes Principal

The flight of a blimp best illustrates a) Pascal's principle. b) Boyle's law. c) Bernoulli's principle. d) Archimedes' principle.

B. 0

The momentum of an object at rest is _____ a) anything other than 0 b) 0 c) the same as if it were moving d) nothing happens

E. the density of both you and the jacket together is less than your density alone

The reason a life jacket helps keep you afloat is a) if you sink, the jacket sinks. b) the jacket has the same density as an average human. c) the jacket makes you weigh less. d) the jacket repels water. e) the density of both you and the jacket together is less than your density alone.

A. straight

The rotational inertia of your leg is greater when your leg is a) straight b) bent c) same either way

E. place part of the body farther from the axis

To increase the moment of inertia of a body about an axis, you must: a) increase the angular acceleration. b) increase the angular velocity. c) decrease the angular velocity. d) make the body occupy less space. e) place part of the body farther from the axis.

C. they have the same non-zero angular speed

Two children are hopefully happy :) riding on a merry-go-round in front of Eva Longoria. Child A is at a greater distance from the axis of rotation than child B. Which child has the larger angular (rotational) speed? a) Child A b) Child B c) They have the same non-zero angular speed. d) They have the same zero angular speed.

50W

Using 1000. J of work, a small object is lifted from the ground floor to the third floor of a tall building in 20.0 seconds. What power was required in this task? Make sure to include proper units.

C. doubling the velocity doubles the magnitude of the momentum and increases the kinetic energy by a factor of four

What does doubling an object's velocity do to its momentum and to its kinetic energy? a) Doubling the velocity doubles the magnitude of the momentum and decreases the kinetic energy by a factor of four. b) Doubling the velocity halves the magnitude of the momentum and decreases the kinetic energy by a factor of four. c) Doubling the velocity doubles the magnitude of the momentum and increases the kinetic energy by a factor of four. d) Doubling the velocity halves the magnitude of the momentum and increases the kinetic energy by a factor of four.

D. quadruples

What happens to the momentum if the velocity and mass is doubled? a) stays the same b) triples c) doubles d) quadruple

C. increases; moment of inertia decreases

When an ice skater is spinning and pulls her hands and (free) foot to her body, her angular velocity (blank) because her (blank). a) increases; mass decreases b) decreases; moment of inertia increases c) increases; moment of inertia decreases d) increases; moment of inertia increases

A. twice as much

When an object is lifted 10 m, it gains a certain amount of potential energy. If the same object is lifted 20 m, its potential energy gain is a) twice as much b) more than four times as much c)four times as much d)less

doubled

When the force that produces an impulse acts for twice as much time, the impulse is

C. 4

When the speed of your car is doubled, by what factor does its kinetic energy increase? a) square root of 2 b) 2. c) 4. d) 8.

C. ice is less dense than water because it has more volume for the same mass

When water freezes, it expands. What does this say about the density of ice compared with the density of water? a) The expansion of water when it freezes to ice changes its volume, not its density. b) Ice is more dense than water because it has more volume for the same mass c) Ice is less dense than water because it has more volume for the same mass.

B. a 10g object with a volume of 1 mL

Which of the following has the largest density? a) a 10-g object with a volume of 10 mL b) a 10-g object with a volume of 1 mL c) a 200-g object with a volume of 200 mL d) a 1-g object with a volume of 10 mL e) All of the densities are the same.

A. an electron is orbiting the nucleus of an atom C. A Yugo (compact car) is moving with a constant speed D. A small flea walking with a constant speed across Fidos back

Which of the following objects have momentum? Include all that apply. a) An electron is orbiting the nucleus of an atom. b) A UPS truck is stopped in front of the school building c) A Yugo (a compact car) is moving with a constant speed. d) A small flea walking with constant speed across Fido's back. e) The high school building rests in the middle of town.

B. the 1000 Kg object

Which one has larger kinetic energy: a 500-kg object moving at 40 m/s or a 1000-kg object moving at 20 m/s? a) the 500 kg object b) the 1000 kg object c) they are the same

B. as the pressure increases, volume decreases at constant temp

Which statement correctly defines Boyle's law? a) As the temperature increases, volume decreases at constant pressure. b) As the pressure increases, volume decreases at constant temperature. c) As the pressure increases, volume increases at constant temperature. d) As the temperature increases, volume increases at constant pressure. e) As the pressure decreases, volume decreases at constant temperature.

A. both of you have the same amount of potential energy

You and your friend want to go to the top of the Eiffel Tower. Your friend takes the elevator straight up. You decide to walk up the spiral stairway, taking longer to do so. Compare the gravitational potential energy (U) of you and your friend, after you both reach the top, assuming that you and your friend have equal masses. a) Both of you have the same amount of potential energy. b) Your friend's U is greater than your U, because she got to the top faster. c) Your U is greater than your friend's U, because you traveled a greater distance in getting to the top.

kinetic energy ex: Depends on the mass of the object and square of its speed Include the proportional constant 1/2 and kinetic energy = 1/2 mass speed If object speed is doubled = kinetic energy is quadrupled.

______ energy of motion

materials

________ transfers heat easily if they have a low specific heat ( good conductors )

mechanical energy

___________ energy do to position, motion, or both

B. decreases

as you rise higher in the earths atmosphere, atmospheric pressure a) increases b) decreases c) stays the same

temperature ** "hot" and "cold" is a temperature difference **

average kinetic energy of molecules moving

Weight

force due to gravity depends on mass ______ depends on mass

thermal energy heat is a transfer of thermal energy **

heat is a transfer of what type of energy?

Mass

how much matter of an object "inertia"

C. both the string and force of gravity

identify the force that fulfills the centripetal force: A bucket (filled with water) is held by a string and whirled in a horizontal circle. a) the string b) force of gravity c) both the string and force of gravity d) centifugal force

C. force of friction

identify the force that fulfills the centripetal force: A car is making a turn along a level roadway. a) force of gravity b) normal force c) force of friction

B. the force of gravity

identify the force that fulfills the centripetal force: A planet is orbiting the sun. a) friction b) force of gravity c) black holes

B. normal force of washing tank

identify the force that fulfills the centripetal force: Clothes move in a circle during the spin cycle in a washing machine. a) Force of gravity b) Normal force of washing tank c) Friction

...

impulse= force X time Ex: A brief force applied over a short time interval produces a smaller change in momentum than the same force applied over a longer time interval. or If you push with the same force for twice the time, you impart twice the impulse and produce twice the change in momentum.

Bernoulli's principal

internal pressure of fluid. if the speed of fluid increases, internal pressure of fluid decreases

Torque

is a measure of how much a force is acting on an object causes that object to rotate

Uniform circular motion

is the motion of an object in a circle with a constant or uniform speed.

electricity

is water a good conductor of heat or electricity?

high specific heat ** boiling water and it taking time to boil and then cool down **

is water a low specific heat or a high specific heat?

B. always positive or 0

kinetic energy is a) always negative or 0 b) always positive or 0

Centripetal Force

maintains an object's circular motion

linear momentum

mass in motion

A. Vector

momentum is a) vector b) scalar

formula

momentum= mass X velocity Ex: A moving boulder has more momentum than a stone rolling at the same speed. A fast boulder has more momentum than a slow boulder. A boulder at rest has no momentum.

B. energy

power depends on ______ a) force b) energy c) acceleration d) momentum

latent heat

specific heat is a transferred heat to do a phase change between a solid, liquid or gas.

height

speed of the pendulum depends on the ____ of an object

A. The moth

suppose you are driving down the highway and a moth crashes into your car. which undergoes the greater acceleration? a) the moth b) the car c) both the same

C. Both the same

suppose you are driving down the highway and a moth crashes into your car. which undergoes the greater change in momentum? a) the moth b) the car c) both the same

C. Both the same Newtons 3rd law

suppose you are driving down the highway and a moth crashes into your car. which undergoes the greater force? a) the moth b) the car c) both the same

C. Both the same F*t=f*t

suppose you are driving down the highway and a moth crashes into your car. which undergoes the greater impulse? a) the moth b) the car c) both the same

radial distance

tangential speed depends on

tangential speed

the average speed is called

C. upward pressure agains the bottom exceeds pressures elsewhere on the object

the buoyant force on a submerged object acts in an upward direction because a) the force is opposite to that of gravity b) it moves in a direction toward floating, which can only be upward c) upward pressure against the bottom exceeds pressures elsewhere on the object d) the density of water increases with increasing depth

A. 20,000N any object that is sitting the weight has to equal the buoyant force

the buoyant force that acts on a 20,000N ship is a) 20,000N b) < 20,000N c) > 20,000N

Rotational Speed (Angular Speed)

the number of rotations or revolutions per unit of time.

momentum

the quantity of motion an object has

specific heat

transferred heat to do a temperature change

A. gravity

what does potential energy depend on? a) gravity b) inertia c) force d) friction

Angular speed

what is the rotational speed

C. Force

what produces acceleration? a) inertia b) velocity c) force d) nothing produces acceleration

in her back ** this is what keeps her from falling forward**

where is the center of mass in a pregnant lady

at different places depending on body orientation

where is the center of mass in your best friend

in the hole

where is the center of mass of a donut

a) ice burg ** no such thing as "heat" **

which can transfer more heat? a) ice burg b) cup of boiling water c) same

a) ice burg ** no such thing as "heat" **

which has more heat? a) ice burg b) cup of boiling water c) same

D. 1g of Lead lead> aluminum lead> iron steel

which of these has the greatest density? a) 10Kg concrete b) 5Kg concrete c) 3Kg of iron d) 1g of Lead

A. Yes, because the car is in motion

will a car with momentum have kinetic energy? a) yes b) no why?