Physics 1560 mid 2
33) The ball rolling down an incline has its maximum potential energy at A) the top. B) a quarter of the way down. C) halfway down. D) the bottom.
a
41) To totally convert a given amount of mechanical energy into heat is A) possible. B) impossible. C) impossible to answer without additional information
a
42) The greater the difference in temperature between the input reservoir and the output reservoir for a heat engine, the A) greater the efficiency. B) less the efficiency. C) Neither - efficiency of a heat engine doesn't depend on temperature difference
a
46) A temperature inversion occurs when the upper layers of air are A) warmer than the lower regions of air. B) cooler than the lower regions of air. C) at the same temperature as lower regions of air.
a
50) The Earth's atmosphere gets most of its heat A) near the surface of the Earth. B) at high altitudes closer to the sun. C) from the Earth's core.
a
1) Which of the following has the largest momentum relative to the Earth's surface? A) a tightrope walker crossing Niagara Falls B) a pickup truck speeding along a highway C) a Mack truck parked in a parking lot D) the Science building on campus E) a dog running down the street
b
17) A job is done slowly, while an identical job is done quickly. Both jobs require the same amount of work, but different amounts of A) energy. B) power. C) effort. D) none of these
b
2) A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is A) zero. B) doubled. C) quadrupled. D) unchanged
b
20) Do 100 J of work in 50 s and your power output is A) 1/2 W B) 2 W. C) 4 W. D) 50 W. E) 5,000 W.
b
21) If an object is raised twice as high, its potential energy will be A) half as much B) twice as much. C) four times as much. D) impossible to determine unless the time is given
b
3) It is correct to say that impulse is equal to A) momentum. B) the change in momentum it produces. C) the force multiplied by the distance the force acts. D) velocity multiplied by time
b
30) A hydraulic press, like an inclined plane, is capable of increasing energy. A) sometimes true B) always false C) always true D) sometimes false
b
35) A block of ice sliding down an incline has its maximum speed at A) the top. B) the bottom. C) halfway down. D) difficult to predict without knowing the slope of the incline E) difficult to predict without knowing the coefficient of friction
b
38) The lowest temperature possible in nature is A) 0 degrees C. B) -273 degrees C. C) 4 K
b
4) The impulse-momentum relationship is a direct result of A) Newton's 1st law. B) Newton's 2nd law. C) Newton's 3rd law. D) Newton's 4th law
b
45) Systems that are left alone, tend to move toward a state of A) less entropy. B) more entropy. C) no entropy
b
48) Entropy is closely related to the A) 1st law of thermodynamics. B) 2nd law of thermodynamics. C) both of these D) neither of these
b
49) Blow on your hand with your open mouth and you feel the warmth of your breath. Pucker your lips so your breath expands as you blow and your breath is A) warmer still. B) cooler. C) neither warmer nor cooler
b
16) If you find that twice as much work is needed to perform a task but it takes twice as much time, the amount of power required is A) twice as much. B) four times as much. C) sixteen times as much. D) unchanged
d
25) An object may have potential energy because of its A) speed. B) acceleration. C) momentum. D) location. E) none of these
d
34) A ball rolling down an incline has its maximum kinetic energy at A) the top. B) halfway down. C) three-quarters of the way down. D) the bottom.
d
39) A volume of air has a temperature of 0 degrees Celsius. An equal volume of air that is twice as hot has a temperature of A) 0 degrees C. B) 64 degrees C. C) 100 degrees C. D) 273 degrees C. E) None of the above choices are correct
d
12) When you are in the way of a fast-moving object and can't get out of its way, you will suffer a smaller force of impact if you decrease its momentum over a A) long time. B) short time. C) same way either way 7.1 Questions About Energy
a
13) If you push for a half hour or a whole hour against a stationary wall A) no work on the wall is done in either case. B) half as much work is done during the half hour. C) twice as much work is done during the half hour. D) it is impossible to determine how much work is done.
a
14) If you push an object twice as far while applying the same force, you do A) twice as much work. B) four times as much work. C) the same amount of work. D) half as much work.
a
15) If you push an object a given distance, while applying twice the force, you do A) twice as much work. B) four times as much work. C) the same amount of work. D) half as much work.
a
19) The power required to exert 1 N force, over a distance of 1 m in 1 second is A) 1 W. B) 2 W. C) 1/3 W. D) 3 W. E) none of these
a
24) An object that has kinetic energy must be A) moving. B) falling. C) at an elevated position. D) at rest. E) none of these
a
26) When bullets are fired from an airplane in the forward direction, the momentum of the airplane will be A) decreased. B) unchanged. C) increased
a
27) A clerk can lift containers a vertical distance of 1 meter or can roll them up a 2 meter-long ramp to the same elevation. With the ramp, the applied force required is about A) half as much. B) twice as much. C) the same. D) four times as much.
a
31) When properly used, a hydraulic press, like a wheel and axle, is capable of multiplying force input. A) always true B) always false C) sometimes true D) sometimes false
a
44) Chinook winds tend to A) warm an environment. B) cool an environment. C) cool deserts at night. D) warm deserts at sunrise.
a
57) Suppose you rapidly stir some raw eggs with an eggbeater. The temperature of the eggs will A) increase. B) decrease. C) remain unchanged.
a
58) Suppose the temperature of the input reservoir in a heat engine doesn't change. As the sink temperature is lowered, the efficiency of the engine A) increases. B) decreases. C) stays the same
a
7) Suppose that a tiny gun made of a strong but very light material fires a bullet that is more massive than the gun itself. For such a weapon A) the target would be safer than the shooter. B) recoil problems would be lessened. C) conservation of energy would not hold. D) conservation of momentum would not hold E) both conservation of energy and momentum would not hold
a
51) Industrialization on Earth eventually heats our surroundings to temperatures that are higher than usual. Industrialization in space habitats using exclusively solar power eventually will thermally pollute the solar system. A) True B) False C) cannot be determined without additional information
b
55) A quantity of water has more entropy when it is A) frozen ice. B) boiling. C) at room temperature.
b
56) One hundred joules of heat is added to a system that performs 60 joules of work. The internal energy change of the system is A) 0 J. B) 40 J. C) 60 J. D) 100 J. E) None of the above choices are correct
b
9) A large heavy truck and a small baby carriage roll down a hill. Neglecting friction, at the bottom of the hill, the baby carriage will have a greater A) speed. B) acceleration. C) momentum. D) all of these E) none of these
E
10) To catch a ball, a baseball player extends the hand forward before impact with the ball and then lets it ride backward in the direction of the ball's motion. Doing this reduces the force of impact on the player's hand principally because the A) force of impact is reduced. B) relative velocity is less. C) time of impact is increased. D) time of impact is decreased. E) none of these
c
11) When you jump from an elevated position you usually bend your knees upon reaching the ground. By doing this, you make the time of the impact about 10 times as great as for a stifflegged landing. In this way the average force your body experiences is A) less than 1/10 as great. B) more than 1/10 as great. C) about 1/10 as great. D) about 10 times as great
c
18) If you do work on an object in one-third the usual time, your power output is A) one third the usual power output. B) the usual power output. C) three times the usual power output. D) impossible to predict without additional information.
c
22) An object lifted 10 meters gains 200 J of potential energy. If the same object is lifted 20 meters, its potential energy gain is A) half as much. B) the same. C) twice as much. D) four times as much. E) more than four times as much.
c
23) A 1000-kg car and a 2000-kg car are hoisted the same distance. Raising the more massive car requires A) less work. B) as much work. C) twice as much work. D) four times as much work. E) more than four times as much work.
c
28) A bow is drawn so that it has 40 J of potential energy. When fired, the arrow will ideally have a kinetic energy that is A) less than 40 J. B) more than 40 J. C) 40 J. D) impossible to predict without additional information
c
32) After rolling halfway down an incline, a marble's kinetic energy is A) less than its potential energy. B) greater than its potential energy. C) the same as its potential energy. D) impossible to determine
c
37) A ball rolling down an incline has its minimum speed A) at the end the incline. B) half way down the incline. C) near the top of the incline. D) impossible to predict without knowing the ball's mass E) impossible to predict without knowing the size of the ball
c
5) The conservation of momentum is most closely related to A) Newton's 1st law. B) Newton's 2nd law. C) Newton's 3rd law. D) Newton's 4th law
c
54) During an adiabatic compression of an ideal gas A) the internal energy of the gas remains constant. B) the temperature of the gas does not change. C) no heat is supplied to or removed from the gas. D) no work is done on the gas. E) None of the above choices are true.
c
6) A rifle recoils while firing a bullet. The speed of the rifle's recoil is small because the A) force against the rifle is smaller than against the bullet. B) momentum is mainly concentrated in the bullet. C) rifle has much more mass than the bullet. D) momentum of the rifle is smaller
c
61) When mechanical work is done on a system, there can be an increase in A) its internal energy. B) its temperature. C) both temperature and internal energy. D) neither temperature nor internal energy
c
8) Two objects have the same size and shape, but one is much heavier than the other. When they are dropped simultaneously from a tower, they reach the ground at the same time, but the heavier one has a greater A) speed. B) acceleration. C) momentum. D) all of these E) none of these
c
40) To wholly convert a given amount of heat energy into mechanical energy is A) possible using a steam engine. B) possible using an atomic reactor. C) possible using a simple machine. D) impossible regardless of the technique used
d
43) The first law of thermodynamics is a restatement of the A) principle of entropy. B) law of heat addition. C) Carnot cycle. D) conservation of energy. E) none of these
d
59) A heat engine would have 100 percent efficiency if its input reservoir were A) 100 times hotter than the exhaust sink. B) 1000 times hotter than the exhaust sink. C) 100 times cooler than the exhaust sink. D) any finite temperature if the exhaust sink were at absolute zero. E) at any finite temperature regardless of the heat sink temperature
d
60) More efficient gasoline engines can be built if A) engines are made to rotate faster. B) a better antifreeze is developed. C) materials are developed that can withstand lower temperatures. D) materials are developed that can withstand higher temperatures. E) None of these - they are already perfectly efficient
d
29) When an automobile is braked to a stop, its kinetic energy is transformed to A) stopping energy. B) potential energy. C) energy of motion. D) energy of rest. E) heat.
e
36) A light aluminum ball and a heavy lead ball of the same size are allowed to roll down an incline. When they are halfway down the incline, they will have identical A) kinetic energies. B) potential energies. C) momentum. D) inertias. E) none of the above choices
e
47) Entropy measures A) temperature at constant pressure. B) temperature at constant volume. C) temperature as pressure increases. D) temperature as volume increases. E) messiness
e
52) Adiabatic processes occur A) only in the atmosphere. B) only in the oceans C) only in the Earth's mantle. D) in both the atmosphere and the oceans E) in the atmosphere, oceans and the Earth's mantle
e
53) When an ideal gas is subjected to an adiabatic process A) no work is done on the gas. B) the temperature of the gas does not change. C) the internal energy of the gas does not change. D) Choices A, B, and C are all true. E) None of the above choices are true.
e