Deck 7: Heat Transfer and Change of Phase

Question 1

A block of wood and a block of copper will feel neither hot nor cold to your touch when they each have

A)equal temperatures.
B)your temperature.
C)equal conductivities.
D)none of the above

Answer 1

B

Question 2

Which of these are good insulators?

A)feathers
B)wood
C)snow
D)all the above
E)none of the above

Answer 2

D

Question 3

If you were caught in freezing weather with only a candle for warmth,you would be warmer in

A)an igloo.
B)a tent.
C)a wooden house.

Answer 3

A

Question 4

Wood is a poor conductor

A)when it is cold.
B)at room temperature.
C)when it is hot.
D)all of the above
E)none of the above

Question 5

When you touch a nail stuck in ice,energy flows from

A)the ice to your hand.
B)your hand to the ice.
C)both of these
D)none of the above

Question 6

In terms of transferring heat,red-hot wooden coals

A)conduct quite well.
B)conduct poorly.
C)radiate poorly.
D)convect poorly.

Question 7

The process of convection occurs in

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

Question 8

The main reason you can walk barefoot on red-hot coals of wood without burning your feet involves

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

Question 9

Conduction has most to do with electrons and atoms

A)bumping into one another.
B)flowing past one another.
C)radiating energy.
D)changing identities.

Question 10

Which of these are good conductors?

A)feathers
B)wood
C)snow
D)all the above
E)none of the above

Question 11

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

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

Question 12

Metals are both good heat and electrical conductors due to

A)similar 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 13

A bare roof of a warmly heated home on a snowy day indicates

A)an unwanted flow of heat.
B)good insulation.
C)a change of phase.
D)all of the above

Question 14

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

A)density.
B)pressure.
C)both of these
D)none of the above

Question 15

Your bare 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)has more thermal energy than tile.
D)all of the above
E)none of the above

Question 16

A good heat conductor is a

A)poor insulator.
B)good insulator.
C)neither of these

Question 17

In practice,a good insulator

A)stops heat flow.
B)slows heat flow.
C)speeds negative heat flow.
D)all of the above

Question 18

Spun glass is a relatively

A)good conductor.
B)poor conductor.
C)both about the same

Question 19

Because of trapped air inside,snow is a

A)poor conductor.
B)good insulator.
C)both of these
D)none of the above

Question 20

A poor conductor of heat is a

A)poor insulator.
B)good insulator.
C)neither

Question 21

The higher the temperature of an object,the

A)longer the wavelengths it radiates.
B)shorter the wavelengths it radiates.
C)none of the above

Question 22

If an object radiates more energy than it absorbs,its

A)thermal energy decreases.
B)temperature decreases.
C)both of these
D)none of the above

Question 23

The gush of steam that issues from the escape valve of a pressure cooker is relatively cool

A)close to the opening.
B)above the opening where vapor is visible.
C)both of these
D)none of the above

Question 24

Blow on your hand and you feel the warmth of your breath.Pucker your lips so your breath expands as you blow and your breath is

A)still warm.
B)cool.
C)neither of these

Question 25

Coastal winds that shift from night to day illustrate

A)conduction.
B)convection.
C)radiation.
D)all about equally

Question 26

Peak frequency as noted on a radiation curve is directly proportional to the

A)frequency of waves emitted.
B)wavelength of waves emitted.
C)temperature of emitted radiation.
D)temperature of the emitter.
E)none of the above

Question 27

An infrared thermometer operates by way of

A)temperature differences.
B)radiant energy invisible to humans.
C)conduction,convection,and radiation.
D)none of the above

Question 28

When air is compressed,its temperature

A)increases.
B)decreases.
C)neither of these

Question 29

If an object absorbs more energy than it emits,its

A)thermal energy decreases.
B)temperature decreases.
C)both of these
D)none of the above

Question 30

The higher the temperature of an object,the

A)higher the frequency of emitted radiation.
B)lower the frequency of emitted radiation.
C)longer the wavelength of emitted radiation.
D)none of the above

Question 31

If a volume of air is warmed,it expands.If a volume of air expands,it

A)warms.
B)cools.
C)neither of these

Question 32

Heat radiation relates mainly to

A)infrared radiant energy.
B)radiation not visible to humans.
C)waves you absorb when near a hot stove.
D)all of the above
E)none of the above

Question 33

Convection currents in the air near a seashore are produced by

A)shifting winds.
B)unequal heating of land and water.
C)varying temperatures.
D)none of the above

Question 34

The higher the frequency of a wave,the

A)shorter the wavelength.
B)longer the wavelength.
C)neither of these

Question 35

Which emits radiation of the highest frequency?

A)a red-hot star
B)the Sun
C)a blue-hot star
D)all the same

Question 36

The average frequency of radiant energy is directly proportional to the

A)Celsius temperature of the emitter.
B)Fahrenheit temperature of the emitter.
C)kelvin temperature of the emitter.
D)all of the above
E)none of the above

Question 37

A substance most commonly emits heat energy by the process of

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

Question 38

Hot steam that issues from a pressure cooker expands and

A)increases in temperature.
B)can cause severe burns.
C)cools.
D)all of the above
E)none of the above

Question 39

A star that is twice as hot as another has twice the

A)Celsius temperature.
B)Fahrenheit temperature.
C)Kelvin temperature.
D)all of the above
E)none of the above

Question 40

Radiant energy emitted by our planet is

A)terrestrial energy.
B)the outcome of radioactivity in Earth's interior.
C)electromagnetic.
D)all of the above

Question 41

To save the most energy when you leave your cool house for an hour or so on a hot day,you should turn the temperature setting on the air conditioner

A)down.
B)up.
C)off.
D)to room temperature.

Question 42

A good reflector of radiation is a

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

Question 43

The silver lining 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 44

Coffee is served at a restaurant before you are ready to drink it.To be hottest when you are ready to drink it,you should add cream

A)right away.
B)at any time.
C)when you are ready to drink the coffee.

Question 45

An apple pie will be a net emitter of energy when its temperature is

A)higher than its surroundings.
B)lower than its surroundings.
C)neither of these

Question 46

If a pizza absorbs more energy than it emits,its temperature

A)decreases.
B)is unaffected.
C)increases.
D)none of the above

Question 47

A red-hot piece of iron will cool slower in a

A)cold room.
B)warm room.
C)same in each

Question 48

Radiant energy from the Sun is composed of shorter wavelengths than radiation from the Earth because the Sun

A)has much more thermal energy.
B)has a higher temperature than the Earth.
C)is an energy source while the Earth is primarily an energy receiver.
D)none of the above

Question 49

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 50

A piece of pizza is normally a net radiator of energy when its temperature is

A)higher than its surroundings.
B)lower than its surroundings.
C)neither of these

Question 51

To minimize heat loss it is best that a teapot be

A)black.
B)silver.
C)depends on size,not color

Question 52

A photovoltaic cell receives energy input primarily by

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

Question 53

If air were a better conductor than it is,nighttimes on Earth would be

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

Question 54

The pupil of your eye is a net

A)absorber of radiant energy.
B)emitter of radiant energy.
C)neither of these

Question 55

Which body continually emits electromagnetic waves?

A)the Sun
B)the Earth
C)you and your classmates
D)all of the above
E)none of the above

Question 56

Newton's law of cooling applies to things that are

A)cooling.
B)warming.
C)both of these
D)none of the above

Question 57

When you leave your warm house for an hour or so on a cold day,to save energy you should turn the thermostat

A)down.
B)up.
C)off.
D)to room temperature.

Question 58

Hot water will cool to room temperature faster in a

A)black pot.
B)silver pot.
C)depends on size,not color

Question 59

Cold water will warm to room temperature faster in a

A)black pot.
B)silver pot.
C)depends on size,not color

Question 60

A watermelon will cool faster when placed in what part of a refrigerator?

A)the freezer compartment
B)the main part of the refrigerator
C)either location should cool the can at the same rate

Question 61

Long ago a runaway greenhouse effect greatly transformed the planet

A)Mercury.
B)Venus.
C)Mars.
D)none of the above

Question 62

The atmosphere becomes opaque to infrared radiation when it

A)increases in temperature.
B)contains excess water vapor and carbon dioxide.
C)radiates high-frequency radiation.
D)none of the above

Question 63

Glass is largely opaque to

A)infrared light.
B)visible light.
C)ultraviolet light.

Question 64

A blueberry pie will be a net absorber of energy when its temperature is

A)higher than its surroundings.
B)lower than its surroundings.
C)none of these

Question 65

The planet Earth loses heat primarily by

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

Question 66

The interior of a greenhouse emits long-wavelength radiation due to its

A)green color.
B)plant cell structure.
C)transparency.
D)relatively low temperature.

Question 67

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.
B)contradicts this.
C)is unrelated to this.

Question 68

Transparency of the atmosphere is lowest for radiation of

A)ultraviolet light.
B)visible light.
C)infrared light.

Question 69

Compared to a glass of ice water with ice,a glass of plain ice-cold water without ice on a warm day will warm up

A)faster.
B)slower.
C)in the same amount of time.

Question 70

If the greenhouse effect on Earth were absent,Earth's average temperature would be about

A)-18°C.
B)appreciably warmer.
C)as it is now.

Question 71

To say you can never change only one thing means that when you change something,

A)some other thing or things change.
B)only one other thing will change.
C)you can't reverse it.

Question 72

Evaporation is a cooling process because

A)heat is radiated during the process.
B)of conduction and convection.
C)the more energetic molecules escape the liquid.
D)none of the above

Question 73

Human activities that warm the Earth's atmosphere are caused by energy

A)production.
B)consumption.
C)both of these
D)none of the above

Question 74

Glass in a florist's greenhouse blocks radiation of relatively

A)high frequencies.
B)low frequencies.
C)all frequencies.

Question 75

Waves emitted by the Sun and terrestrial wave emissions are

A)the same except for their frequencies and wavelengths.
B)entirely different kinds of waves.
C)identical.

Question 76

To say that evaporation is a cooling process is to say that the

A)water left behind is cool.
B)air cools as water warms.
C)condensation is minimum.

Question 77

Glass in a florist's greenhouse acts as a one-way valve by

A)blocking the flow of light energy.
B)blocking unwanted radiation.
C)being transparent only to lower-frequency waves.
D)allowing high-frequency waves to enter and blocking low-frequency waves from exiting.

Question 78

The molecules in a room-temperature glass of water jostle around at

A)various speeds.
B)much the same speed.
C)constant speeds.

Question 79

Which is not a phase of matter?

A)solids
B)liquids
C)gases
D)vacuum

Question 80

When evaporation occurs in a dish of water,the molecules remaining in the water

A)are less energetic.
B)have decreased average speeds.
C)are at a lower temperature.
D)all of the above