Deck 6: Heat

Question 1

Which of the following normally warms up faster when heat is applied?

A)water
B)iron
C)glass
D)wood

Answer 1

B

Question 2

Before ice can form on a lake, all the water in the lake must be cooled to

A)0°C.
B)4°C.
C)a value slightly below 0°C.

Answer 2

B

Question 3

The reason that the white-hot sparks that strike your skin from a 4th-of-July-type sparkler don't harm you is because

A)they have a low temperature.
B)the energy per molecule is very low.
C)the energy per molecule is high, but the total energy transferred is small.

Answer 3

C

Question 4

Place a 1-kg block of iron at 40°C into a kilogram of water at 20°C and the final temperature of the two becomes

A)less than 30°C.
B)at or about 30°C.
C)more than 30°C.

Question 5

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.

Question 6

If the specific heat capacity of water were lower than it is, ponds in the cold of winter would be

A)more likely to freeze.
B)less likely to freeze.
C)neither A nor B

Question 7

Heat energy is measured in units of

A)joules.
B)calories.
C)both A and B

Question 8

A substance that heats up relatively quickly has a

A)high specific heat capacity.
B)low specific heat capacity.

Question 9

The temperature at the bottom of Lake Tahoe, high in the Sierra Mountains in California, at this moment is

A)below 4°C.
B)exactly 4°C.
C)above 4°C.
D)uncertain.

Question 10

The fact that desert sand is very hot in the day and very cold at night is evidence that sand has a

A)low specific heat capacity.
B)high specific heat capacity.

Question 11

The fact that a thermometer "takes its own temperature" illustrates

A)thermal equilibrium.
B)energy conservation.
C)the difference between heat and thermal energy.
D)the fact that molecules are constantly moving.

Question 12

Pour a liter of water at 40°C into a liter of water at 20°C and the final temperature of the two becomes

A)less than 30°C.
B)at or about 30°C.
C)more than 30°C.

Question 13

Heat energy travels from an object with a high

A)thermal energy to an object with a lower thermal energy.
B)temperature to an object with a lower temperature.
C)Both of the above, for they say essentially the same thing.

Question 14

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)low specific heat capacities.
B)high specific heat capacities.

Question 15

Atoms and molecules are always

A)moving.
B)still, unless they are forming a chemical bond.
C)changing.
D)appearing and disappearing.

Question 16

Compared to a giant iceberg, a hot cup of coffee has

A)more thermal energy and higher temperature.
B)higher temperature, but less thermal energy.
C)a greater specific heat and more thermal energy.
D)none of the above

Question 17

Ice tends to form at the

A)surface of bodies of water.
B)bottom of bodies of water.

Question 18

The moderate temperatures of islands throughout the world has much to do with water's

A)poor conductivity.
B)vast supply of thermal energy.
C)high specific heat capacity.
D)high evaporation rate.
E)absorption of solar energy.

Question 19

Microscopic slush in water tends to make the water

A)more dense.
B)less dense.

Question 20

Ice has a lower density than water because ice

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

Question 21

Two identical blocks of iron, one at 10°C and the other at 20°C, are put in contact. Suppose the cooler block cools to 5°C and the warmer block warms to 25°C. This would violate the

A)first law of thermodynamics.
B)second law of thermodynamics.
C)both A and B
D)neither A nor B

Question 22

A piece of iron and a cup of water both have the same temperature. If they are heated so the thermal energy of each doubles,

A)the water will have the higher temperature.
B)the iron will have the higher temperature.
C)both will have the same temperature.
D)not enough information given to say

Question 23

When ice floats in water, a small part of it extends above the surface. Interestingly enough, the volume of ice that extends above the surface is equal to the volume of the

A)water the ice displaces.
B)vast number of open spaces in the hexagonal ice crystals.
C)both A and B
D)neither A nor B

Question 24

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.

Question 25

Heating Earth's atmosphere is caused by energy

A)production.
B)consumption.
C)both A and B
D)neither A nor B

Question 26

When work is done by a system and no heat added to it, the temperature of the system

A)increases.
B)decreases.
C)remains unchanged.

Question 27

The lowest temperature possible in nature is

A)0°C.
B)-73°C.
C)4 K.

Question 28

A volume of air has a temperature of 0°C. An equal volume of air that is twice as hot has a temperature of

A)0°C.
B)2°C.
C)100°C.
D)273°C.
E)none of the above

Question 29

On a chilly 10°C day, your friend who likes cold weather wishes it were twice as cold. Taken literally, this temperature would be

A)10°C.
B)5°C.
C)0°C.
D)131.5°C.
E)141.5°C.

Question 30

It is possible to wholly convert a given amount of heat energy into mechanical energy.

A)True
B)False

Question 31

Suppose you rapidly stir some raw eggs with an eggbeater. The temperature of the eggs will

A)increase.
B)decrease.
C)remain unchanged.

Question 32

Consider a piece of metal that is at 5°C. If it is heated until it has twice the thermal energy, its temperature will be

A)10°C.
B)273°C.
C)278°C.
D)283°C.
E)556°C.

Question 33

As a system becomes more disordered, entropy

A)increases.
B)decreases.
C)remains the same.

Question 34

When 100 J of heat is added to a system that performs 60 J of work, the thermal energy change of the system is

A)0 J.
B)40 J.
C)60 J.
D)100 J.
E)none of the above

Question 35

If you run a refrigerator in a closed room with the refrigerator door open, the room temperature will

A)increase.
B)decrease.
C)remain unchanged.

Question 36

Consider a piece of metal that is at 10°C. If it is heated until it has twice the thermal energy, its temperature will be

A)20°C.
B)273°C.
C)293°C.
D)566°C.
E)none of the above

Question 37

Entropy is closely related to the

A)first law of thermodynamics.
B)second law of thermodynamics.
C)both A and B
D)neither A nor B

Question 38

When mechanical work is done on a system, there can be an increase in its

A)thermal energy.
B)temperature.
C)both A and B
D)neither A nor B

Question 39

Aluminum has a specific heat capacity more than twice that of copper. Place equal masses of aluminum and copper wire in a flame and the one to undergo the fastest increase in temperature will be

A)copper.
B)aluminum.
C)both the same

Question 40

It is possible to totally convert a given amount of mechanical energy into heat.

A)True
B)False

Question 41

If you stake out a plot of land with a steel tape on a very hot day, the amount of land you will have will be

A)smaller.
B)larger.
C)no different.

Question 42

Which of the following contracts most when the temperature is decreased? Equal volumes of

A)iron.
B)wood.
C)water.
D)helium.
E)All contract the same.

Question 43

When water at 4°C is heated it expands. When water at 4°C is cooled, it

A)contracts.
B)expands.
C)neither A nor B

Question 44

Consider a sample of water at 0°C. If the temperature is slightly increased, the volume of water

A)expands.
B)contracts.
C)remains the same.

Question 45

Which of the following expands most when the temperature is increased? Equal volumes of

A)iron.
B)wood.
C)ice water.
D)helium.
E)All expand the same.

Question 46

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 gets hotter before copper.
B)copper gets hotter before iron.
C)copper expands more than iron.
D)iron expands more than copper.
E)none of the above

Question 47

Metals are both good heat conductors and also good electrical conductors because of the

A)similarity between thermal and electrical conductive properties.
B)looseness of outer electrons in metal atoms.
C)relatively high densities of metals.
D)high elasticity of metals.
E)ability of metals to transfer energy easily.

Question 48

Your feet feel warmer on a rug than on a tile floor because the rug

A)is usually warmer than tile.
B)is a better insulator than tile.
C)for the same mass has more thermal energy than tile.
D)all of the above
E)none of the above

Question 49

If you measure a plot of land with a steel tape on a hot day, your measurements of the plot will be

A)smaller than actual.
B)larger than actual.

Question 50

When an iron ring is heated, the hole becomes

A)smaller.
B)larger.
C)neither smaller nor larger.

Question 51

A substance can absorb heat energy by the process of

A)conduction.
B)convection.
C)radiation.
D)all of the above

Question 52

During a very cold winter, water pipes sometimes burst. The reason for this is

A)the ground contracts when colder, pulling pipes apart.
B)water expands when freezing.
C)water contracts when freezing.
D)the thawing process releases pressure on the pipes.
E)none of the above

Question 53

Energy transfer by convection is primarily restricted to

A)solids.
B)liquids.
C)gases.
D)fluids.
E)none of the above

Question 54

Which of the following expands most when the temperature is lowered? Equal volumes of

A)iron.
B)wood.
C)helium.
D)water at 4°C.
E)None expand when the temperature is lowered.

Question 55

As a piece of metal with a hole in it cools, the diameter of the hole

A)increases.
B)decreases.
C)remains the same.

Question 56

Consider a closed, sealed can of air placed on a hot stove. The contained air undergoes an increase in

A)mass.
B)pressure.
C)temperature.
D)all of the above
E)two of the above

Question 57

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 A nor B

Question 58

Which of the following contracts most when the temperature is increased? Equal volumes of

A)iron.
B)wood.
C)ice water.
D)helium.
E)None of these contract when heated.

Question 59

Consider a metal ring with a gap cut in it. When the ring is heated, the gap

A)becomes narrower.
B)becomes wider.
C)retains its size.

Question 60

A good heat conductor is a

A)poor insulator.
B)good insulator.
C)neither A nor B

Question 61

A good absorber of radiation is a

A)good emitter of radiation.
B)poor emitter of radiation.
C)good reflector.
D)none of the above

Question 62

At the same temperature, which move with the greater speed in the air?

A)very light molecules
B)heavier molecules
C)All will have equal average speeds.

Question 63

The silver coating on the glass surfaces of a Thermos bottle reduces energy that is transferred by

A)conduction.
B)convection.
C)radiation.
D)friction.
E)none of the above

Question 64

Newton's law of cooling applies to objects that are

A)cooling.
B)heating.
C)both A and B
D)none of the above

Question 65

It is commonly thought that a can of beverage will cool faster in the coldest part of a refrigerator. Knowledge of Newton's Law of Cooling

A)supports this common knowledge.
B)shows this common knowledge is false.

Question 66

Objects that radiate relatively well,

A)absorb radiation relatively well.
B)reflect radiation relatively well.
C)both A and B
D)neither A nor B

Question 67

An object will normally be a net radiator of energy when its thermal energy is

A)more than that of its surroundings.
B)less than that of its surroundings.
C)Can't say, because thermal energy is not temperature.

Question 68

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

Question 69

A water-filled paper cup held in a flame will not catch fire. This is because

A)the inside of the paper is wet.
B)water is an excellent conductor of heat.
C)paper is a poor conductor of heat.
D)the paper cup cannot become appreciably hotter than the water it contains.

Question 70

When a volume of air is compressed, its temperature

A)increases.
B)decreases.
C)neither increases nor decreases.

Question 71

The pupil of your eye is a net

A)absorber of radiant energy.
B)emitter of radiant energy.

Question 72

Warm air rises because faster moving molecules tend to move to regions of less

A)density.
B)pressure.
C)both A and B

Question 73

One of the main reasons people can walk barefoot on red-hot coals of wood without burning their feet has to do with

A)low temperature of the coals.
B)low thermal conductivity of the coals.
C)mind over matter techniques.

Question 74

If a poor absorber of radiation were a good emitter, its temperature would be

A)less than its surroundings.
B)more than its surroundings.
C)the same as its surroundings.

Question 75

Hot water will cool to room temperature faster in a

A)black pot.
B)silver pot.
C)depends more on the size of the pots than their color

Question 76

The higher the temperature of an object, the

A)longer the wavelengths it radiates.
B)shorter the wavelengths it radiates.

Question 77

If air were a better conductor than it is, at nighttime the earth would be

A)considerably colder.
B)considerably warmer.
C)not appreciably different in temperature.

Question 78

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.

Question 79

If an object radiates more energy than it absorbs, its

A)thermal energy decreases.
B)temperature decreases.
C)both A and B
D)neither A nor B

Question 80

An object will normally be a net radiator of energy when its temperature is

A)higher than its surroundings.
B)lower than its surroundings.
C)neither A nor B