Physics Module 3 (chapter 7-8)

If you double the absolute temperature of a star, its power output increases by a factor of A. 2 B. 4 C. 8 D. 16

D. 16

Which temperature scale has 373 as the boiling point of water? A. F B. C C. centigrade D. kelvin

D. kelvin

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 the mountain top. B) faster at sea level. C) faster at both places. D) no differently than it did before the increase.

D. no differently than it did before

People on a space ship are traveling around the universe observing stars with different temperatures. Which of the following stars has the lowest surface temperature? A. bluish star B. yellowish star C. the sun D. reddish star

D. reddish star

If you double the radiating surface area of a star, its power output increases by a factor of A. 2 B. 4 C. 8 D. 16

A. 2

"Two objects in thermal equilibrium with a third object are in thermal equilibrium with each other." Which Law of Thermodynamics is this? A. Zeroth B. First C. Second D. Third

A. Zeroth

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

A. a low specific heat

Compared to a glass of ice water with ice in it, 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

A. faster

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

A. from your finger to the ice

A shiny, white transparent surface prevents heat transfer because A. it has emissivity of zero & reflects all light B. it has emissivity of 1 & reflects all light C. it has emissivity of zero & absorbs all light D. it has emissivity of 1 & absorbs all ligth

A. it has emissivity of zero & reflects all light

If the specific heat 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 more nor less likely to freeze

A. more likely to freeze

Suppose you try to cool your home in the summer by letting heat flow from your house to your neighbors home. You will A. not get far because of zeroth law of thermodynamics B. not get far because of first law of thermodynamics C. have a cool house in a couple hours D. have a warmer house in a couple hours

A. not get far, zeroth law of thermodynamics

When gas is changed to a liquid state the gas A. releases energy B. absorbs energy C. neither D. both

A. releases energy absorbed --> S/L/G <--- released

Ice tends to form first at the A. surface of bodies of water B. bottom of bodies of water C. surface or bottom depending on depth

A. surface of bodies of water

The fact that a thermometer "takes its own temperature" illustrates A. thermal equilibrium B. energy conservation C. the differences between heat & internal energy D. the fact that molecules are constantly moving

A. thermal equilibrium

When water vapor condenses on the inside of a window, the room becomes slightly A. warmer B. cooler C. neither

A. warmer

Suppose you walk on red-hot coals with bare feet. If bits of the coals do not stick to your feet, it would be best if your feet are A. wet B. dry C. warm D. cold

A. wet

Which could burn the most? A. 100 g of water at 100 degrees C B. 100 g of steam at 100 degrees C C. both are equal

B. 100 g of steam at 100 degrees C

Before ice can form on a lake, all the water in the lake must be cooled to A. zero degrees C B. 4 degrees C C. minus 32 degrees C D. None of the above

B. 4 degrees C (ice expands at 4 degrees & after)

Near the top of a mountain water in an open pot boils at A. a higher temperature than at sea level B. a lower temperature than at sea level C. the same temperature as sea level

B. a lower temperature than at sea level (Denver = 95 degrees )

When a solid is changed to a liquid, the solid A. releases energy B. absorbs energy C. neither D. both

B. absorbs energy

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

B. at or about 30 degrees C

The gulf stream is one of natures ways of transferring energy through A. conduction B. convection C. transmission D. radiation

B. convection

Wind is one of nature's ways of transferring energy through A. conduction B. convection C. transmission D. radiation

B. convection

Melting snow A) warms the surrounding air. B) cools the surrounding air. C) neither warms nor cools the surrounding air.

B. cools the surrounding air

Consider a sample of ice at 0 degrees C. If the temperature is decreased, the volume of the ice A) increases B) decreases C) stays the same

B. decreases

Consider a sample of water at 0 degrees C. If the temperature is slightly increased the volume of the water A. increases B. decreases C. remains the same

B. decreases

When water at 4 degrees C is heated slightly it expands. When water at 4 degrees C is cooled slighted it A. contracts B. expands C. neither

B. expands (expands both ways)

For increased atmospheric pressure, the boiling temperature of a liquid A. goes down B. goes up C. remains at 100 degrees C

B. goes up

It is a hot summer day and your friend's apartment has no air conditioning. However, a brand new refrigerator lies unopened in the center of the living room. Being a creative person, your friend closes all the doors and windows of the apartment, unpacks the refrigerator, plugs it in, and turns it on. Your friend then opens the refrigerator door and uses a small fan to circulate the air past the refrigerator and throughout the room. After the refrigerator has operated for a few minutes, the average temperature in the room is A. lower than it was before B. higher than it was before C. the same as it was before

B. higher than it was before

Housing and natural animal insulation works because A. insulating materials are poorer heat conductors than air B. insulating materials trap air and prevent convection C. insulating materials prevent radiation D. insulating materials reflect radiation

B. insulating maters trap air & prevent convection

Which of the following normally warms up fastest when heat is applied? A. water B. iron C. glass D. wood

B. iron

When an iron ring is heated, the hole becomes A. smaller B. larger C. neither D. depends on thickness

B. larger (iron heat expands)

Lead sinkers actually float on the surface of liquid mercury. Which takes up more space: 1 kg of mercury or 1 kg of lead? A. mercury B. lead C. neither

B. lead

The glowing bars refer the metal bars that hold wood in a fireplace and they are transmitting heat energy by A. radiation only B. radiation & conduction C. conduction only D. convection

B. radiation & conduction

People fighting forest fires carry emergency tents that have shiny aluminum outer surfaces. If there is trouble, a fire fighter can lie under the tent to block the heat from burning trees overhead. The tent helps because A. conduction carries heat downward toward the fire fighter & aluminum tent conduct that heat into the ground B. radiation carries heat downward toward the fire fighter & aluminum tent reflects most of the radiation C. convection carries heat downward toward the fire fighter & aluminum tent blocks heat carried by convection D. both conduction & radiation carry heat downward & aluminum tent blocks the heat

B. radiation carries heat downward & aluminum tent reflects the radiation

When liquids change to a solid state, the liquid A. absorbs energy B. releases energy C. neither D. both

B. releases energy

Evaporation is a cooling process because A. heat is radiated during the process B. the more energetic molecules are able to escape the liquid C. the temperature of the remaining liquid increases

B. the more energetic molecules are able to escape the liquid

You fill two identical mugs with coffee, but the coffee in one mug is at a higher temperature than that in the other mug. You place the two mugs simultaneously in a microwave oven and turn it on briefly. As a result, you add 1 Joule of thermal energy to each mug. Which mug experiences the larger increase in entropy (if any)? A. The two mugs experience equal increase in entropy B. The mug containing colder coffee experiences larger increase in entropy C. Neither mug experiences an increase in entropy D. The mug containing hotter coffee experiences large increase in entropy

B. the mug containing colder coffee experiences larger increase in entropy

You are riding in a hot air balloon. You have not used the burner for some time and the balloon begins to sink. Assuming no air is allowed to leave or enter the balloon, A. average density of the balloon remained constant and the buoyant force on the balloon became less than its weight B. average density of the balloon became greater than the surrounding air and the buoyant force remained constant C. average density of the balloon became greater than the surrounding air and buoyant force became less than its weight

C. average density of balloon becomes greater than air & buoyant force becomes less than its weight

Heat energy is measured in units of A. joules B. calories C. both A & B D. kelvin

C. both A & B

Steam burns are more damaging than burns caused by boiling water because steam A. gives up additional energy when it condenses B. has more energy per kg than boiling water C. both A & B

C. both A & B

The first law of thermodynamics is a restatment of the law of A. conservation of momentum B. thermal equilibrium C. conservation of energy D. averages

C. conservation of energy

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

C. does not change

Why are good thermal conductors generally good electric conductors also? A. heat and electricity are the same things B. the molecules in both dont move around much C. electron motion is responsible for determining both properties

C. electron motion is responsible for determining both properties

Which of the following quantities is not conserved? A. energy B. angular momentum C. entropy D. momentum

C. entropy

Two equal sized buckets are filled to the top with water. One of the buckets has a piece of wood floating in it, making its total weight A. more than the weight of the other bucket B. less than the weight of the other bucket C. equal to the weight of the other bucket

C. equal to the weight of the other bucket

Why does an ice cube feel cold? A. heat from your hand enters the cube by convection B. cold from the cube enters your hand by convection C. heat from your hand enters the cube by conduction D. cold from the cube enters your hand by conduction

C. heat from your hand enters the cube by conduction

Which temperature scale has 273 as the boiling point of water A. F B. C C. no scale D. kelvin

C. no scale

Freezing is a ___ that requires energy ____ for the melting system A. phase transition; input B. chemical change; input C. phase transition; release D. chemical change; release

C. phase transition; release

Entropy of an isolated system can never decrease. Which law of thermodynamics is this? A. zeroth B. first C. second D. third

C. second

When cooking a potato in a conventional oven it is useful to stick a nail in it, which makes it cook faster. This is because A. nail is a good radiator of heat B. nail promotes convection in the potato C. nail is a good conductor of heat D. nail gets hotter

C. the nail is a good conductor of heat

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

E. covered with salt