CHAPTER 16 (PHYSICS)

When your foot stands on a tile floor, thermal energy always flow

From either your foot or the tile depending on the temperature of the tile

A good absorber of radiation is a

Good emitter of radiation

What type of gas absorbs and re-emits infrared radiation?

Greenhouse gases

The reason the Suns radient energy is of shorter wavelengths than the Earths is because the Sun

Has a higher temperature than the Earth

The relation f-t tells us that high temperature sources emit electromagnetic waves of

High frequency

In a mixture of hydrogen gas, oxygen gas and nitrogen gas, the molecules with the greatest average speed are those of

Hydrogen

When a volume of air is compressed, its temperature

Increases

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

Is a better insulator than tile

Which of the following would best describe the conductive properties of wood?

It is a good insulator

What happens to the conductive properties of wood when it gets very hot?

It will continue to remain a good insulator

Hydrogen and oxygen molecules in a gas sample have the same temperature. This means the hydrogen molecules, on the average, have the same

Kinetic energy, but more speed

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

Less than its surroundings

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

Looseness of outer electrons in metal atoms

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

Low thermal conductivity of the coals

Ceiling fans can make you feel cooler in a warm room. Do ceiling fans reduce room temperature?

NO

A good reflector of radiation is a

Poor absorber of radiation

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

Very light molecules

How would you walk on red hot coals without getting your feet burned?

Walk fast

Which will undergo the greater rate of cooling-a red hot poker in a warm oven or a red hot poker in a cold room (or do the cool at the same rate?)

A red hot poker in a cold room

If you are able to grab a hot pan and pull it out by the handle without burning yourself, what kind of handle must the pan have, and why?

A wooden handle, because it is a better insulator

A liter of hot water will cool to room temperature faster in a

Black pot

Cold water will warm to room temperature faster in a

Black pot

Which body glows with electromagnetic waves?

Both the sun and Earth

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

Considerably colder

Newtons law of cooling applies to objects that undergo

Cooling or warming

When air rapidly expands, its temperature normally

Decreases

Heat travels from the sun to the Earth by the process of

Radiation

The planet Earth loses heat mainly by

Radiation

Substances absorb heat energy by the process of

Radiation, convection and conduction

Suppose you are served coffee at a restaurant before you are ready to drink it. In order for it to be the hottest when you are ready for it, you should add cream

Right away

Relatively speaking, do high frequency waves have long wavelengths or short wavelengths?

Short wavelengths

It is commonly thought that a can of beverage will cool faster in the coldest part of a refrigerator. Knowledge of Newtons law of cooling

Supports this common knowledge

How would decreasing the percentage of greenhouse gases affect the amount of infrared radiation reflected by the atmosphere back toward Earth?

The amount of infrared radiation would decrease

How would increasing the density of air in the atmosphere affect the amount of infrared radiation returned by the atmosphere back toward Earth?

The amount of infrared radiation would increase

Both black and white road surfaces absorb sunlight. At the end of a sunny day the warmer road surface will be

The black surface

Why is one able to walk on red hot coals without getting ones foot burned?

The coals are not good conductors of heat

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

The paper cup cannot become appreciably hotter than the water it contains

The higher temperature of an object

The shorter the wave lengths it radiates