Exam 3

thermal conduction mainly involves...

electrons

When most substances are heated, molecules inside move faster and take up more space, resulting in thermal

expansion

compared with radiation from the sun, the terrestrial radiation has a lower...

frequency

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

higher temperature, but less internal energy.

The color of heat is _____

infrared

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

more than 30°C.

Translational motion is characterized by

motion that carries a molecule from one place to another

Heat energy travels from an object with a high

temperature to an object with a lower temperature

Temperature is generally proportional to a substance's

average translational kinetic energy

temperature is generally proportional to a substance's...

average translational kinetic energy

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

becomes wider.

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

at or about 30°C

In which is the temperature greater?

boiling-hot tea in a cup

Heat energy is measured in units of

both calories and joules

newton's law of cooling applies to objects that...

cool and warm up

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

copper

When a bimetallic bar made of copper and iron strips is heated, the bar bends toward the iron strip. The reason for this is

copper expands more than iron.

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

decreases

If glass expanded more than mercury, then the column of mercury in a mercury thermometer would fall when the temperature

decreases

It is important that the two metals that compose a bimetallic strip have

different rates of expansion.

the amount of heat transferred to a system can be measured in...

either calories or joules

Internal energy is greater in a

fire-engine pail of boiling-hot tea.

When you touch a hot potato with your finger, energy flows

from the potato to your finger

When you touch a cold piece of ice with your finger, energy flows

from your finger to the ice

In most cases, which expands more for comparable changes in temperature?

gases

The fact that gasoline overflows a full tank on a hot day is evidence that

gasoline expands more with increasing temperature than its tank

To say that water has a high specific heat capacity is to say that water

gives off a lot of energy in cooling

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

helium

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

helium

A substance that heats up relatively slowly has a

high specific heat capacity

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

high specific heat capacity.

Materials composed of molecules that absorb large amounts of energy in the form of internal vibrations and rotations have

high specific heats.

Which of these expands when the temperature is lowered?

ice water

When the temperature of a strip of iron is increased, the length of the strip

increases

as liquid evaporates, its temperature ________

increases

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

iron

Which unit represents the most energy?

joule

The amount of heat transferred to a system can be measured in

joules and calories

Temperature is most closely related to molecular

kinetic energy

When an iron ring is heated, the hole becomes

larger

When we enlarge a photograph of an iron ring, the image of the hole becomes

larger

Hot sand cools off faster at night than vegetation. Compared with vegetation, sand's specific heat capacity is...

less

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

less than 30°C

Hot sand cools off faster at night than plants and vegetation. Then, the specific heat capacity of sand is

less than that of plants.

One of water's interesting thermal properties is that when heated it takes a relatively

long time in changing temperature.

The principal source of Earth's internal energy is...

radioactivity

when relatively slow-moving molecules condense from the air, the temp of the remaining air tends to...

remain unchanged

If the specific heat capacity of water were lower than it is, a nice hot bath would be a

shorter experience

If the specific heat capacity of water were lower than it is, a watermelon in a picnic cooler would cool in a

shorter time

T or F: for an engine to produce useable work, the exhaust (output) temperature must be lower than the input temperature

true

T or F: heat never spontaneously flows from a cooler to a warmer body

true

T or F: heat transfer via conduction generally occurs via materials that are poor electrical insulators

true

T or F: the entropy of the universe is increasing

true

T or F: the greater the temp difference between 2 objects, the faster the rate of heat transfer

true

the greenhouse gases that contribute to global warming are...

water vapor and carbon dioxide

when the temp of a strip of iron is increased, the length of the strip

may increase and may decrease

microscopic slush in water tends to make the water...

more dense

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

more likely to freeze.

The Farenheit and Centigrade temperature scales have the same numerical value at _____ degrees

-40

The _______ is the amount of heat needed to raise 1 pound of water by one degree F

BTU

Which temperature scales have equal sized degrees

Celsius and Kelvin

State the third law of thermodynamics

In natural processes, high-quality energy tends to transform into lower-quality energy-order tends to disorder

The air in your room is composed of molecules that have

a wide variety of speeds

If you wanted to raise the internal energy of a bucket of 20°C water, you could

add 25°C water in the bucket.

The quantity of heat that a substance can transfer relates to its

all of the above

Heat transfer involving the movement of a hot/cold medium is called _______

convection

heat is simply another word for....

internal energy that flows from hot to cold

Aluminum has a higher specific heat capacity than iron. This means that for equal masses of aluminum and iron, the metal that heats up the fastest is

iron

The white-hot sparks from a 4th-of-July-type sparkler that strike your skin transfer

little energy to you despite of their high temperature.

heat transfer that occurs in the absence of a medium is ________

radiation

the surface of planet earth loses energy to outer space due mostly to...

radiation

an object that absorbs energy well also..

radiates well

as long as water and steam are present the temperature of the water is _____

100 degrees celsius

Which of these temperatures is likely when a container of water at 20°C is mixed with water at 28°C?

22°C

Room temperature on the Kelvin scale is about

300K

The amount of heat needed to raise the temperature of 1 gram of water by 1°C is

4.19 joules

When 10 grams of hot water cool by 1°C, the amount of heat given off is

4.19 joules

Which temperature scale has the smallest sized degrees

Fahrenheit

A temperature difference of 10 Celsius degrees is also equal to a temperature difference of 10 on the

Fahrenheit scale

T or F: heat transfer via conduction is directly proportional to the area of the material

True

T or F: the higher the specific heat of a material, the more heat it takes to raise its temperature

True

T or F: the non-metric unit of heat is the BTU

True

heat comes from the sun to earth by the process of...

radiation

If you measure the width of an outdoor barn with a steel tape on a very cold day, your measured width will be

a bit long

If you measure the distance between two telephone poles with a steel tape on a very hot day, your measured distance will be

a bit short

White-hot sparks from a 4th-of-July-type sparkler that strike your skin have relatively

all of the above

The fact that desert sand is very hot in the day and very cold at night is evidence that the specific heat capacity of sand is relatively

low

a high-temp source radiates relatively

low frequencies of radiation

A substance that heats up relatively quickly has a

low specific heat capacity

A substance that cools down faster than others has a

low specific heat capacity.

The temperature at the top of a waterfall is lower, same, or higher than at the bottom

lower because it gains energy as it falls

The specific heat capacity is highest for substances that absorb or release large quantities of heat for correspondingly

small temperature changes.

A substance with a high thermal inertia has a high

temperature, in many cases.

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

temperature.

In terms of thermal expansion it is important that

the fillings in your teeth expand at the same rate as teeth.

How do down-filled parkas keep you warm?

the fluff/feathers trap air inside, the air heats up inside jacket and keep you warm

Tomatoes have a higher specific heat capacity than dough. This means that when you bite into a hot pizza

the tomato sauce feels hotter than the dough

Heat is simply another word for

thermal energy that flows from hot to cold

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

thermal equilibrium

The kind of molecular motion that mostly relates to the temperature of a substance is

translational motion