Test 4: Review B

Question 1

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) both ways.

Answer 1

*A) from your finger to the ice.

Question 2

Compared to a giant iceberg, a hot cup of coffee has
A) a greater specific heat and more internal energy.
B) more internal energy and higher temperature.
C) higher temperature, but less internal energy.
D) none of these

Answer 2

*C) higher temperature, but less internal energy.

Question 2

Ice has a lower density than water because ice
A) is made of open-structured, hexagonal crystals.
B) molecules vibrate at lower rates than water molecules.
C) molecules are more compact in the solid state.
D) density decreases with decreasing temperature.

Answer 2

*A) is made of open-structured, hexagonal crystals.

Question 3

Before ice can form on a lake, all the water in the lake must be cooled to
A) 4 degrees C.
B) minus 32 degrees C.
C) zero degrees C.
D) None of the above are true. Ice can form at the surface regardless of the water temperature below.

Answer 3

*A) 4 degrees C.

Question 3

A substance that heats up relatively quickly has a
A) high specific heat.
B) high conductivity.
C) low specific heat.
D) low conductivity.

Answer 3

*C) low specific heat.

Question 4

As a piece of metal with a hole in it cools, the diameter of the hole
A) decreases.
B) increases.
C) remains the same.

Answer 4

*A) decreases.

Question 4

If glass expanded more than mercury, then the column of mercury in a mercury thermometer would rise when the temperature
A) increases.
B) decreases.
C) neither of these

Answer 4

*B) decreases.

Question 5

Consider a closed, sealed can of air placed on a hot stove. The contained air undergoes an increase in
A) temperature.
B) pressure.
C) mass.
D) two of these.

Answer 5

*D) two of these.

Question 6

When water at 4 degrees C is heated it expands. When water at 4 degrees C is cooled, it
A) expands.
B) contracts.
C) neither contracts nor expands.

Answer 6

*A) expands.

Question 7

A temperature difference of 10 degrees Celsius is also equal to a temperature difference of 10 on the
A) Fahrenheit scale.
B) Kelvin scale.
C) both
D) neither of these

Answer 7

*B) Kelvin scale.

Question 8

The white-hot sparks that strike your skin from a 4th-of-July-type sparkler do not 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.

Answer 8

*B) the energy per molecule is high, but little energy is transferred because of the few molecules in the spark.

Question 9

The fact that desert sand is very hot in the day and very cold at night is evidence that sand has
A) no specific heat.
B) a high specific heat.
C) a low specific heat.

Answer 9

*C) a low specific heat.

Question 10

Pour a liter of water at 40 degrees C into a liter of water at 20 degrees C and the final temperature of the two becomes
A) more than 30 degrees C.
B) less than 30 degrees C.
C) at or about 30 degrees C.

Answer 10

*C) at or about 30 degrees C.

Question 11

Substances absorb heat energy by the process of
A) convection.
B) conduction.
C) radiation.
D) all of these

Answer 11

*D) all of these

Question 12

Metals are both good heat conductors and good electrical conductors because of the
A) relatively high densities of metals.
B) high elasticity of metals.
C) ability of metals to transfer energy easily.
D) similarity between thermal and electrical conductive properties.
E) looseness of outer electrons in metal atoms.

Answer 12

*E) looseness of outer electrons in metal atoms.

Question 13

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

Answer 13

*B) is a better insulator than your tile.

Question 14

Objects that radiate relatively well,
A) reflect radiation relatively well.
B) absorb radiation relatively well.
C) both
D) neither of these

Answer 14

*B) absorb radiation relatively well.

Question 15

Cold water will warm to room temperature faster in a
A) black pot.
B) silver pot.
C) depends more on the size of the pots than their color

Answer 15

*A) black pot.

Question 16

An object will normally be a net radiator of energy when its temperature is
A) lower than its surroundings.
B) higher than its surroundings.
C) neither of these

Answer 16

*B) higher than its surroundings.

Question 17

The planet Earth loses heat mainly by
A) convection.
B) conduction.
C) radiation.
D) all of these

Answer 17

*C) radiation.

Question 18

One of the main reasons one can walk barefoot on red-hot coals of wood without burning the feet has to do with
A) mind over matter techniques.
B) low temperature of the coals.
C) low thermal conductivity of the coals.

Answer 18

*C) low thermal conductivity of the coals.

Question 19

If a volume of air is warmed, it expands. If a volume of air expands, it
A) warms.
B) cools.
C) neither warms nor cools.

Answer 19

*B) cools.

Question 20

A good absorber of radiation is a
A) good reflector.
B) good emitter of radiation.
C) poor emitter of radiation.
D) none of these

Answer 20

*B) good emitter of radiation.

Question 21

The reason the sun’s radiant energy is of shorter wavelengths than the Earth’s is because the sun
A) has much more internal energy.
B) is an energy source while the Earth is primarily an energy receiver.
C) has a higher temperature than the Earth.
D) all of these
E) none of these

Answer 21

*C) has a higher temperature than the Earth.

Question 22

If you were caught in freezing weather with only a candle for heat, you would be warmer in
A) a wooden house.
B) an igloo.
C) a car.
D) a tent.

Answer 22

*B) an igloo.

Question 23

To say that evaporation is a cooling process is to say that the
A) more energetic particles remain in the water.
B) the less energetic particles escape.
C) more energetic particles escape.

Answer 23

*C) more energetic particles escape.

Question 23

The molecules in a room-temperature glass of water jostle around at
A) much the same rates of speed.
B) a very small range of speeds.
C) a great variety of speeds.

Answer 23

*C) a great variety of speeds.

Question 23

When a solid is changed to a liquid state, the solid
A) absorbs energy.
B) releases energy.
C) neither releases nor absorbs energy.
D) both releases and absorbs energy.

Answer 23

*A) absorbs energy.

Question 24

When heat is added to boiling water, its temperature
A) increases.
B) decreases.
C) does not change.

Answer 24

*C) does not change.

Question 25

Increased air pressure on the surface of hot water tends to
A) prevent boiling.
B) promote boiling.
C) Neither choice A nor choice B is true.
D) Choice A and choice B are both true.

Answer 25

*A) prevent boiling.

Question 25

Food cooked in boiling water at a mountain top cooks slower than when cooked at sea level. If the temperature under the pot of boiling water is increased, the food will cook
A) faster at sea level.
B) faster at the mountain top.
C) faster at both places.
D) no differently than it did before the increase.

Answer 25

*D) no differently than it did before the increase.

Question 25

Water will evaporate quicker if it
A) Choices C, D, and E are all correct.
B) One or two of the choices below are not correct.
C) is spread out in a thin sheet.
D) is surrounded by dry air.
E) is preheated to 100 degrees C.

Answer 25

*A) Choices C, D, and E are all correct.

Question 25

Hot water has a relatively high rate of
A) condensation.
B) conductivity.
C) convection.
D) evaporation.

Answer 25

*D) evaporation.

Question 26

When snow forms in clouds, the surrounding air
A) warms.
B) cools.
C) neither warms nor cools.

Answer 26

*A) warms.

Question 27

A refrigerator
A) causes internal energy to disappear.
B) changes heat into cold.
C) produces cold.
D) removes internal energy from inside the refrigerator.
E) none of these

Answer 27

*D) removes internal energy from inside the refrigerator.

Question 28

On a humid day, water condenses on the outside of a glass of ice water. This phenomenon occurs mainly because of
A) the porosity of glass.
B) capillary action.
C) the saturation of cooled air.
D) evaporation.
E) adhesion of water molecules to glass.

Answer 28

*C) the saturation of cooled air.

Question 29

Ice is put in a cooler to cool the contents. To speed up the cooling process, the ice can be
A) drained of ice water periodically.
B) wrapped in newspaper.
C) kept out of contact with the food.
D) kept in one solid chunk.
E) covered with salt.

Answer 29

*E) covered with salt.

Question 29

To wholly convert a given amount of heat energy into mechanical energy is
A) possible using an atomic reactor.
B) possible using a steam engine.
C) possible using a simple machine.
D) impossible regardless of the technique used.

Answer 29

*D) impossible regardless of the technique used.

Question 30

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.

Answer 30

*A) warmer than the lower regions of air.

Question 30

The lowest temperature possible in nature is
A) -273 degrees C.
B) 0 degrees C.
C) 4 K.

Answer 30

*A) -273 degrees C.

Question 30

Systems that are left alone, tend to move toward a state of
A) more entropy.
B) less entropy.
C) no entropy.

Answer 30

*A) more entropy.

Question 31

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.

Answer 31

*A) cooler.

Question 31

A quantity of water has more entropy when it is
A) at room temperature.
B) boiling.
C) frozen ice.

Answer 31

*B) boiling.

Question 32

Entropy can be
A) neither created nor destroyed.
B) sometimes destroyed but never created.
C) created but not destroyed.

Answer 32

*C) created but not destroyed.

Question 33

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) 100 J.
B) 40 J.
C) 0 J.
D) 60 J.
E) None of the above choices are correct.

Answer 33

*B) 40 J.

Question 34

A heat engine would have 100 percent efficiency if its input reservoir were
A) 100 times hotter than the exhaust sink.
B) any finite temperature if the exhaust sink were at absolute zero.
C) 1000 times hotter than the exhaust sink.
D) 100 times cooler than the exhaust sink.
E) at any finite temperature regardless of the heat sink temperature.

Answer 34

*B) any finite temperature if the exhaust sink were at absolute zero.

Question 35

When a system does work and no heat is added to the system, its temperature
A) increases.
B) decreases.
C) remains unchanged.

Answer 35

*B) decreases.

Question 36

An adiabatic process is characterized by the absence of
A) entropy.
B) temperature change.
C) pressure change.
D) heat exchange.
E) None of the above choices are true.

Answer 36

*D) heat exchange.

Question 37

If a blob of air is swept upward, with no heat input or output, its temperature
A) increases.
B) decreases.
C) remains the same.

Answer 37

*B) decreases.

Question 38

The ideal efficiency for a heat engine operating between temperatures of 2700 K and 300 K is
A) 80%.
B) 24%.
C) 89%.
D) 10%.

Answer 38

*C) 89%.