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MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) The two measurements necessary for calculating average speed are
A) velocity and time.
B) distance and acceleration.
C) acceleration and time.
D) distance and time.
E) velocity and distance.
1)
2) A horse gallops a distance of 10 kilometers in a time of 30 minutes. It's average speed is
A) 20 km/h.
B) 40 km/h.
C) 15 km/h.
D) 30 km/h.
2)
3) Twelve seconds after starting from rest, an object falling freely will have a speed of
A) 10 m/s.
B) 100 m/s.
C) 50 m/s.
D) more than 100 m/s.
3)
4) If an object moves with constant acceleration, its velocity must
A) change by the same amount each second.
B) always decrease.
C) be constant also.
D) change by varying amounts depending on its speed.
4)
5) If a car increases its velocity from zero to 60 km/h in 10 seconds, its acceleration is
A) 3 km/h/s.
B) 600 km/h/s.
C) 10 km/h/s.
D) 60 km/h/s.
E) 6 km/h/s.
5)
6) If a rocket initially at rest accelerates at a rate of 50 m/s2 for one minute, its speed will be
A) 500 m/s.
B) 50 m/s.
C) 3600 m/s.
D) 3000 m/s.
6)
7) A ball tossed vertically upward rises, reaches its highest point, and then falls back to its starting
point. During this time the acceleration of the ball is always
A) opposite its velocity.
B) in the direction of motion.
C) directed upward.
D) directed downward.
7)
8) In each second of fall, the distance a freely falling object will fall is
A) about 10 m.
B) about 5 m.
C) the same, but not 5 m or 10 m.
D) increasing.
E) none of these.
8)
1
9) When a rock thrown straight upwards gets to the exact top of its path, its
A) velocity is zero and its acceleration is zero.
B) velocity is about 10 m/s and its acceleration is about 10 meters per second per second.
C) velocity is zero and its acceleration is about 10 meters per second per second.
D) velocity is about 10 m/s and its acceleration is zero.
E) none of these
9)
10) If you drop an object, it will accelerate downward at a rate of 9.8 meters per second per second. If
you instead throw it downwards, its acceleration (in the absence of air resistance) will be
A) less than 9.8 meters per second per second.
B) greater than 9.8 meters per second per second.
C) 9.8 meters per second per second.
10)
11) A sheet of paper can be withdrawn from under a container of milk without toppling it if the paper
is jerked quickly. This best demonstrates that
A) there is an action-reaction pair of forces.
B) gravity tends to hold the milk carton secure.
C) the milk carton has inertia.
D) the milk carton has no acceleration.
E) none of these
11)
12) A package falls off a truck that is moving at 30 m/s. Neglecting air resistance, the horizontal speed
of the package just before it hits the ground is
A) zero.
B) less than 30 m/s but larger than zero.
C) more than 30 m/s.
D) about 30 m/s.
E) More informationis needed for an estimate.
12)
13) If your automobile runs out of fuel while you are driving the engine stops but you do not come to
an abrupt stop. The concept that most explains why is
A) acceleration.
B) gravity.
C) resistance.
D) inertia.
13)
14) Whirl a rock at the end of a string and it follows a circular path. If the string breaks, the tendency of
the rock is to
A) continue to follow a circular path.
B) follow a straight-line path.
C) revolve in a smaller circle
D) increase its speed
14)
15) If no external forces are acting on a moving object it will
A) continue moving at the same velocity.
B) continue moving at the same speed.
C) move slower and slower until it finally stops.
15)
16) A force is a vector quantity because it has both
A) action and reaction counterparts.
B) mass and acceleration.
C) magnitude and direction.
16)
2
17) An object is propelled along a straight-line path by a force. If the net force were doubled, the
object's acceleration would be
A) the same.
B) half as much.
C) twice as much.
D) four times as much.
E) none of these.
17)
18) If an object's mass is decreasing while a constant force is applied to the object, the acceleration
A) increases.
B) remains the same.
C) decreases.
18)
19) An object is pulled northward by a force of 10 N and at the same time another force of 15N pulls it
southward. The magnitude of the resultant force on the object is
A) 5 N.
B) 150 N.
C) 25 N.
D) 0 N.
19)
20) The force of friction on a sliding object is 10 newtons. The applied force needed to maintain a
constant velocity is
A) 10 N.
B) more than 10 N.
C) less than 10 N.
20)
21) An apple weighs 1 N. When held at rest above your head, the net force on the apple is
A) 0 N.
B) 9.8 N.
C) 0.1 N.
D) 1 N.
E) none of these
21)
22) An apple at rest weighs 1 N. The net force on the apple when it is in free fall is
A) 0.1 N.
B) 1 N.
C) 9.8 N.
D) 0 N.
E) none of these
22)
23) Whenever the net force on an object is zero, its acceleration
A) may be less than zero.
B) may be more than zero
23)
C) is zero.
24) A 1-kg mass at the earth's surface weighs
A) 10.8 N.
B) 4.9 N.
C) 1 N.
D) 9.8 N.
E) none of these
24)
25) A car has a mass of 1000 kg and accelerates at 2 meters per second per second. What is the
magnitude of the net force exerted on the car?
A) 1500 N
B) 2000 N
C) 1000 N
D) 500 N
E) none of these
25)
3
26) A tow truck exerts a force of 3000 N on a car, accelerating it at 2 meters per second per second.
What is the mass of the car?
A) 1500 kg
B) 1000 kg
C) 3000 kg
D) 500 kg
E) none of these
26)
27) Wherever the is an action force, there must be a reaction force which
A) is exactly equal in magnitude.
B) is slightly larger in amplitude than the action force.
C) always acts in the same direction.
D) is slightly smaller in magnitude than the action force.
27)
28) An archer shoots an arrow. Consider the action force to be exerted by the bowstring against the
arrow. The reaction to this force is the
A) friction of the ground against the archer's feet.
B) air resistance against the bow.
C) arrow's push against the bowstring.
D) grip of the archer's hand on the bow.
E) combined weight of the arrow and bowstring.
28)
29) Which of the following has the largest momentum relative to the Earth?
A) a pickup truck speeding along a highway
B) a Mack truck parked in a parking lot
C) a tightrope walker crossing Niagara Falls
D) the Science building on campus
E) a dog running down the street
29)
30) It is correct to say that impulse is equal to
A) the force multiplied by the distance the force acts.
B) the change in momentum.
C) momentum.
D) velocity multiplied by time
30)
31) A rifle recoils while firing a bullet. The speed of the rifle's recoil is small because the
A) momentum of the rifle is smaller.
B) momentum is mainly concentrated in the bullet.
C) rifle has much more mass than the bullet.
D) force against the rifle is smaller than against the bullet.
31)
32) In order 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) time of impact is increased.
C) relative velocity is less.
D) time of impact is decreased.
E) none of these
32)
4
33) A 4 kg ball has a momentum of 12 kg m/s. What is the ball's speed?
A) 48 m/s
B) 3 m/s
C) 4 m/s
D) 12 m/s
E) none of these
33)
34) A ball is moving at 3 m/s and has a momentum of 48 kg m/s. What is the ball's mass?
A) 12 kg
B) 4 kg
C) 144 kg
D) 16 kg
E) none of these
34)
35) If you push for a half hour or a whole hour against a stationary wall,
A) twice as much work is done during the half hour.
B) no work is done in either case.
C) half as much work is done during the half hour.
D) it is impossible to determine how much work is done.
35)
36) If you push an object a given distance, while applying twice the force, you do
A) four times as much work.
B) the same amount of work.
C) half as much work.
D) twice as much work.
36)
37) 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) effort.
B) power.
C) energy.
D) none of these
37)
38) If you do work on an object in one-third the usual time, your power output is
A) the usual power output.
B) one third the usual power output.
C) three times the usual power output.
D) impossible to predict without additional information.
38)
39) Do 100 J of work in 50 s and your power output is
A) 5,000 W.
B) 2 W.
C) 1/2 W
D) 50 W.
E) 4 W.
39)
40) If an object is raised twice as high, its potential energy will be
A) twice as much.
B) half as much
C) four times as much.
D) impossible to determine unless the time is given.
40)
41) An object that has kinetic energy must be
A) at rest.
B) falling.
C) at an elevated position.
D) moving.
E) none of these
41)
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42) An object may have potential energy because of its
A) speed.
B) momentum.
C) acceleration.
D) location.
E) none of these
42)
43) 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) 40 J.
B) less than 40 J.
C) more than 40 J.
D) impossible to predict without additional information
43)
44) When a car is braked to a stop, its kinetic energy is transformed to
A) potential energy.
B) energy of rest.
C) stopping energy.
D) heat.
E) energy of motion.
44)
45) The ball rolling down an incline has its maximum potential energy at
A) the bottom.
B) a quarter of the way down.
C) the top.
D) halfway down.
45)
46) A ball rolling down an incline has its maximum kinetic energy at
A) the top.
B) the bottom.
C) three-quarters of the way down.
D) halfway down.
46)
47) A TV set is pushed a distance of 2 m with a force of 20 N. How much work is done on the set?
A) 20 J
B) 10 J
C) 800 J
D) 40 J
E) 2 J
47)
48) A 2-kg mass is held 4 m above the ground. What is the approximate potential energy of the mass
with respect to the ground?
A) 80 J
B) 6 J
C) 8 J
D) 32 J
E) none of these
48)
49) A car moves 4 times as fast as another identical car. Compared to the slower car, the faster car has
A) 8 times the KE.
B) 12 times the KE.
C) 4 times the KE.
D) 16 times the KE.
49)
50) Newton discovered
A) that gravity is universal.
50)
B) gravity.
C) neither
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51) According to Newton, the greater the masses of interacting objects, the
A) greater the force between them by the square of the masses.
B) greater the gravitational force between them.
C) less the gravitational force between them.
51)
52) According to Newton, doubling the distance between two interacting objects
A) multiplies by 2 the gravitational force between them.
B) divides by 4 the gravitational force between them.
C) divides by 2 the gravitational force between them.
D) multiplies by 4 the gravitational force between them.
52)
53) If the mass of the Earth somehow increased with no change in radius, your weight would
A) decrease.
B) stay the same.
C) increase also.
53)
54) A black hole is
A) simply the remains of a giant star that has undergone gravitational collapse.
B) a small region that contains the mass of many galaxies.
C) an empty region of space with a huge gravitational field.
54)
55) An asteroid exerts a 360-N gravitational force on a nearby spacecraft. If the spacecraft moves to a
point 3 times as far from the center of the asteroid, the force will be
A) 40 N.
B) 360 N.
C) 1080 N.
D) 120 N.
E) zero.
55)
56) The amount of gravitational force that acts on the space shuttle while in orbit is
A) almost as much as the shuttle's weight on the Earth's surface.
B) the same as the shuttle's weight on the Earth's surface.
C) nearly zero.
56)
57) Two objects move toward each other because of gravity. As the objects get closer and closer, the
force between them
A) decreases, then increases.
B) remains constant.
C) increases.
D) increases, then decreases.
E) decreases.
57)
58) If you drop a stone into a hole drilled all the way to the other side of the Earth (neglect the molten
core), the stone will
A) speed up until it reaches the other side of the Earth.
B) slow down until it reaches the center.
C) speed up until it gets to the center of the Earth.
D) come to an abrupt stop at the center of the Earth.
58)
59) Inside a freely-falling runaway elevator, your
A) apparent weight is zero.
B) gravitational interaction with the Earth is zero.
C) acceleration is zero.
D) all of these
E) none of these
59)
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60) The reason the moon does not crash into the Earth is that the
A) Earth's gravitational field is weak at the moon.
B) moon has less mass than the Earth.
C) gravitational pull of other planets keeps the moon up.
D) moon has a sufficient tangential speed.
E) none of these
60)
61) The factor most directly responsible for making a black hole invisible is its
A) mass.
B) surface escape velocity.
C) size.
D) color.
E) none of these
61)
62) When a star collapses to form a black hole, its mass
A) remains the same.
B) increases.
C) decreases.
62)
63) Which pulls on the oceans of the Earth with the greater force?
A) the sun
B) the moon
C) Both pull the same.
64) Which is most responsible for the ocean tides?
A) the sun
B) the moon
C) Both contribute equally.
63)
64)
65) The main reason ocean tides exist is that the pull of the moon
A) and sun are in conjunction at high tides and in opposition at low tides.
B) and the sun on the oceans are in opposite directions.
C) is greater on oceans closer to the moon and less on oceans farther from the moon.
D) is greater on the Earth because the moon is closer to Earth.
E) none of these
65)
66) During an eclipse of the sun the high ocean tides on Earth are
A) extra low.
B) extra high.
C) not particularly different.
66)
67) The best time for digging clams (when the low tide is extra low) is during the time of the
A) new or full moon.
B) quarter moon.
C) half moon.
D) none of these times in particular
67)
68) There are no tides to be seen in the community swimming pool because
A) it is shallow compared to the ocean.
B) they are masked by the much stronger pull of Earth gravity.
C) gravitation on the small mass of water is negligibly small.
D) all parts of it are practically the same distance from the moon.
E) But there are at nighttime.
68)
8
69) Which of the following is not a vector quantity?
A) speed
B) acceleration
C) velocity
D) None are vector quantities.
E) All are vector quantities.
69)
70) An airplane that flies at 100 km/h in a 100 km/h hurricane crosswind has a ground speed of
A) 100 km/h.
B) 141 km/h.
C) 0 km/h.
D) 200 km/h.
70)
Figure 10-B
71) A rock is thrown upward at 50 degrees with respect to the horizontal. As it rises, its vertical
component of velocity
A) decreases.
B) remains unchanged.
C) increases.
71)
72) A rock is thrown upward at 50 degrees with respect to the horizontal. As it rises, its horizontal
component of velocity
A) decreases.
B) remains unchanged.
C) increases.
72)
73) An Earth satellite is simply a projectile
A) freely falling around the earth.
B) approaching the earth from outer space.
C) floating motionless in space near the earth.
73)
74) Earth satellites are typically more than 100 km high so as to be above the Earth's
A) atmosphere.
B) gravitational field.
C) both of these
74)
75) A projectile is fired vertically from the surface of the Earth at 8 km/s. The projectile will
A) rise and fall back to the Earth's surface.
B) escape from the Earth.
C) follow an uncertain path.
D) go into circular orbit about the Earth.
75)
76) An Earth satellite is in an elliptical orbit. The satellite travels fastest when it is
A) farthest from the Earth.
B) nearest the Earth.
C) It travels at constant speed everywhere in orbit.
76)
77) The fastest moving planet in a solar system is
A) the planet farthest from the sun.
B) the most massive planet.
C) the smallest planet.
D) the planet nearest the sun.
E) any planet, for they all move at the same speed.
77)
9
78) Consider a monkey wrench released at rest at the far edge of the solar system. Suppose that it drops
to the Earth by virtue of only Earth gravity. It will strike the Earth's surface with a speed of about
A) 11 km/s.
B) 9.8 m/s.
C) 8 km/s.
D) the speed of light.
78)
79) Minimal orbital speed about the Earth is about 8 km/s. Minimal orbital speed about the moon
would be
A) more than 8 km/s.
B) less than 8 km/s.
C) about 8 km/s.
79)
80) A rocket fired vertically at 11.2 km/s will escape the Earth. If it is instead fired horizontally at this
speed, free from obstructions, will it still escape the Earth?
A) Yes
B) No
C) There's no way to tell.
80)
81) How many different elements are in a water molecule?
A) one
B) two
C) three
81)
D) four
E) none
82) If we doubled the magnifying power of the most powerful optical microscope in the world, we
would
A) be able to see individual atoms.
B) still not be able to see or photograph an atom.
C) be able to photograph individual atoms, even though we couldn't see them.
82)
83) Which of the following statements is true?
A) A large atom can be photographed with the aid of an ordinary microscope.
B) There are only about 100 different kinds of atoms that combine to form all substances.
C) An atom is the smallest particle known to exist.
D) There are thousands of different kinds of atoms that account for a wide variety of substances.
E) None of these statements are true.
83)
84) What makes an element distinct?
A) the number of electrons
B) the number of neutrons
C) the number of protons
D) the total mass of all the particles
E) none of these
84)
85) In an electrically neutral atom, the number of protons in the nucleus is balanced by an equal
number of
A) orbital electrons.
B) quarks.
C) neutrons.
D) all of these
E) none of these
85)
86) The smallest particle of those listed below is
A) a neutron.
B) a proton.
C) a molecule.
D) an atom.
E) a quark.
86)
10
87) Solid matter is mostly empty space. The reason solids don't fall through one another is because
A) of gravitational forces.
B) of nuclear forces.
C) of electrical forces.
D) atoms are constantly vibrating, even at absolute zero.
E) none of these
87)
88) If an astronaut landed on a planet made of antimatter, there would be an explosion and
A) an amount of planet matter equal to that of the astronaut would annihilate.
B) the planet would annihilate.
C) the astronaut would annihilate.
D) the astronaut and an equal amount of the planet would both annihilate.
88)
89) Assuming all the atoms exhaled by Julius Caesar in his last dying breath are still in the atmosphere,
then we probably breathe one of those atoms with each
A) day.
B) single breath.
C) ten years.
D) month.
E) It depends some people still breathe a few of Caesar's atoms every day, while others
wouldn't breathe one for an entire year.
89)
90) Nuclei of atoms that make up a newborn baby were made in
A) the mother's womb.
B) ancient stars.
C) the food the mother eats before giving birth.
D) the Earth.
E) none of these
90)
91) The reason a granite block is mostly empty space is that the atoms in the granite are
A) in perpetual motion.
B) not as close together as they could be.
C) mostly empty space themselves.
D) invisible.
E) held together by electrical forces.
91)
92) Compared to a bar of pure gold, the density of a pure gold ring is
A) less.
B) much more.
C) slightly more.
92)
11
D) the same.
Figure 12-A
93) If a loaf of bread is compressed, its
A) density increases.
B) molecules become harder.
C) surface tension becomes less.
D) density decreases.
E) none of these
93)
Figure 12-B
94) When weight is applied to the top of a stone arch, all of the stone blocks in the arch undergo
A) tension.
B) compression.
C) change of phase.
D) expansion.
94)
95) You wish to bolt a sign to a horizontal I-beam supporting a bridge. You will weaken the beam least
if you drill the bolt-holes through the
A) web.
B) lower flange.
C) upper flange.
D) All these will have the same effect.
95)
96) Doubling the thickness (diameter) of a rope will multiply its strength by
A) 1/2.
B) 1.
C) 2.
D) 3.
96)
E) 4.
97) A wooden block has a mass of 1000 kg and a volume of 2 cubic meters. What is the block's density?
A) 100 kg per cubic meter
B) 1000 kg per cubic meter
C) 500 kg per cubic meter
D) 200 kg per cubic meter
E) none of these
97)
98) A metal block has a density of 5000 kg per cubic meter and a mass of 15,000 kg. What is its volume?
A) 5 cubic meters
B) 3 cubic meters
C) 0.33 cubic meters
D) 15 cubic meters
E) none of these
98)
12
99) Which has more skin, an elephant or a mouse?
A) mouse
B) elephant
C) typically, both the same
99)
100) Which has more skin compared to its body weight, an elephant or a mouse?
A) elephant
B) mouse
C) typically, both the same
100)
101) Tripling the linear size of an object multiplies its area by
A) 9 and its volume by 18.
B) 3 and its volume by 9.
C) 27 and its volume by 81.
D) 9 and its volume by 27.
E) none of these
101)
102) Which geometrical shape has the least surface area for a given volume?
A) pyramid
B) sphere
C) cube
D) cylinder
E) none of these
102)
103) Which cooks faster in boiling oil?
A) a whole potato.
B) a sliced potato.
104) In cold weather, your hands will be warmer if you wear
A) gloves.
B) mittens.
C) Both cook the same.
C) Both will be the same.
103)
104)
105) When you touch a cold piece of ice with your finger, energy flows
A) from your finger to the ice.
B) from the ice to your finger.
C) actually, both ways.
105)
106) A substance that heats up relatively quickly has a
A) high specific heat.
C) high conductivity.
B) low conductivity.
D) low specific heat.
106)
107) Heat energy is measured in units of
A) calories.
C) Choices A and B are both true.
B) joules.
D) Choices A and B are both false.
108) The moderate temperatures of islands throughout the world has much to do with water's
A) high specific heat.
B) absorption of solar energy.
C) vast supply of internal energy.
D) high evaporation rate.
E) poor conductivity.
13
107)
108)
109) Before ice can form on a lake, all the water in the lake must be cooled to
A) minus 32 degrees C.
B) zero degrees C.
C) 4 degrees C.
D) None of the above are true. Ice can form at the surface regardless of the water temperature
below.
109)
110) When an iron ring is heated, the hole becomes
A) larger.
B) smaller.
C) neither smaller nor larger.
D) either smaller or larger, depending on the ring thickness.
110)
111) When a bimetallic bar made of copper and iron strips is heated, the bar bends toward the iron strip.
The reason for this is
A) iron expands more than copper.
B) copper expands more than iron.
C) copper gets hotter before iron.
D) iron gets hotter before copper.
E) none of these
111)
112) During a very cold winter, water pipes sometimes burst. The reason for this is
A) water expands when freezing.
B) water contracts when freezing.
C) the thawing process releases pressure on the pipes.
D) the ground contracts when colder, pulling pipes apart.
E) none of these
112)
113) Room temperature on the Kelvin scale is about
A) 300 K.
B) 100 K.
C) 400 K.
D) 200 K.
E) more than 400 K.
113)
114) The white-hot sparks that strike your skin from a 4th-of-July-type sparkler don't harm you
because
A) they have a low temperature.
B) the energy per molecule is high, but little energy is transferred because of the few molecules
in the spark.
C) the energy per molecule is very low.
114)
115) Some molecules are able to absorb large amounts of energy in the form of internal vibrations and
rotations. Materials composed of such molecules have
A) high specific heats.
B) low specific heats.
C) none of the above
115)
116) The fact that desert sand is very hot in the day and very cold at night is evidence that sand has
A) a high specific heat.
B) a low specific heat.
C) no specific heat.
116)
14
117) Substances absorb heat energy by the process of
A) convection.
B) conduction.
C) radiation.
D) all of these
117)
118) Metals are both good heat conductors and good electrical conductors because of the
A) looseness of outer electrons in metal atoms.
B) similarity between thermal and electrical conductive properties.
C) ability of metals to transfer energy easily.
D) high elasticity of metals.
E) relatively high densities of metals.
118)
119) A good heat conductor is
A) a poor insulator.
B) a good insulator.
C) neither a poor nor a good insulator.
119)
120) Your feet feel warmer on a rug than on your tile floor because your rug
A) for the same mass has more internal energy than your tile.
B) is a better insulator than your tile.
C) is usually warmer than your tile.
D) all of these
E) none of these
120)
121) Energy transfer by convection is primarily restricted to
A) solids.
B) gases.
C) liquids.
D) fluids.
E) none of these
121)
122) The higher the temperature of an object,
A) the shorter the wavelengths it radiates.
B) the longer the wavelengths it radiates.
C) makes no difference in the wavelengths it radiates
122)
123) If a solid object radiates more energy than it absorbs, its
A) internal energy decreases.
B) internal energy and temperature decrease.
C) temperature decreases.
D) None of the above choices are true.
123)
124) A liter of hot water will cool to room temperature faster in a
A) silver pot.
B) black pot.
C) red pot.
D) depends more on the size of the pot than its color
124)
125) The planet Earth loses heat mainly by
A) radiation.
B) convection.
C) conduction.
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D) all of these
125)
126) One of the main reasons one can walk barefoot on red-hot coals of wood without burning the feet
has to do with
A) low temperature of the coals.
B) mind over matter techniques.
C) low thermal conductivity of the coals.
126)
Figure 16-B
127) A Thermos bottle has double glass walls with silver coating on the glass surfaces that face one
another. The silver coating reduces the energy that is transferred by
A) convection.
B) conduction.
C) friction.
D) radiation.
E) none of these
127)
128) If a volume of air is warmed, it expands. If a volume of air expands, it
A) cools.
B) warms.
C) neither warms nor cools.
128)
129) When a volume of air is compressed, its temperature
A) increases.
B) decreases.
C) neither increases nor decreases.
129)
130) A good absorber of radiation is a
A) good emitter of radiation.
C) poor emitter of radiation.
B) good reflector.
D) none of these
130)
131) Evaporation is a cooling process and condensation is
A) a cooling process also.
B) a warming process.
C) neither a warming nor cooling process.
131)
132) Evaporation is a cooling process because
A) of conduction and convection.
B) the more energetic molecules are able to escape the liquid.
C) the temperature of the remaining liquid decreases.
D) heat is radiated during the process.
E) none of these
132)
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133) We are warmed by condensation because water molecules in the air that strike our bodies
A) gain kinetic energy as they change state.
B) form an insulating layer on our bodies.
C) transfer some of their kinetic energy to us.
133)
134) When a solid is changed to a liquid state, the solid
A) absorbs energy.
C) neither releases nor absorbs energy.
134)
B) releases energy.
D) both releases and absorbs energy.
135) When heat is added to boiling water, its temperature
A) decreases.
B) increases.
C) does not change.
135)
136) For increased atmospheric pressure, the boiling temperature of a liquid
A) remains at 100 degrees C.
B) goes down.
C) goes up.
136)
137) Near the top of a mountain, water in an open pot boils at
A) the same temperature as at sea level.
B) a lower temperature than at sea level.
C) a higher temperature than at sea level.
D) None of the above choices are true.
137)
Figure 17-B
138) Food in a pressure cooker is cooked faster because of the
A) greater rate of bubble formation in the water.
B) higher temperature.
C) increased internal energy in the water.
D) Choices A, B, and C are all true.
E)
138)
139) If you want to cook eggs by boiling them while in the mountains, then compared to sea-level
cooking, you should
A) boil the eggs for a shorter time.
B) boil the eggs for a longer time.
C) use a hotter flame.
D) None of the above choices are true.
139)
140) The lowest temperature possible in nature is
A) 4 K.
B) -273 degrees C.
140)
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C) 0 degrees C.
141) To wholly convert a given amount of heat energy into mechanical energy is
A) possible using an atomic reactor.
B) possible using a simple machine.
C) possible using a steam engine.
D) impossible regardless of the technique used.
141)
142) 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.
142)
143) The first law of thermodynamics is a restatement of the
A) conservation of energy.
B) law of heat addition.
C) Carnot cycle.
D) principle of entropy.
E) none of these
143)
144) Systems that are left alone, tend to move toward a state of
A) more entropy.
B) less entropy.
C) no entropy.
144)
145) 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) cooler.
B) warmer still.
C) neither warmer nor cooler.
145)
146) The ideal efficiency for a heat engine operating between temperatures of 2700 K and 300 K is
A) 89%.
B) 24%.
C) 80%.
D) 10%.
E) none of these
146)
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