Ch. 22 test

good emitters of radiant energy are also good __

absorbers

define insulator

any material that is a poor conductor of heat and that delays the transfer of heat

when a molecule collides with a molecule that is receding, its rebound speed after the collision is __ than it was before the collision

less

suppose you have a box, painted white inside, which is closed except for a hole 2 centimeters wide. Circle the letter beside the sentence that explains why the hole appears black

light that enters is reflected and partly absorbed so many times that little is left to come out

objects of everyday temperatures emit waves mostly in the __ end of the infrared region

long-wavelength

do objects at low temperatures emit waves with a longer or shorter wavelength than objects with higher temperature?

longer

imagine stepping with one bare foot onto metal and with the other bare foot onto wood. Explain why the metal feels cool and the wood feels warm, even though they have the same temperature

metal is a good conductor, but wood is a poor conductor. heat easily moves out of your foot into the cooler metal. Little heat moves out of your foot into the wood, so your foot does not sense that it is touching something cooler

what are the best conductors

metals

an insulator cannot totally prevent heat from getting through, but instead just reduces the rate at which heat penetrates. true or false?

true

as air rises and expands, it collides with more molecules that are receding than are approaching. True of false?

true

conduction occurs without any overall transfer of matter. true or false?

true

__ is the main greenhouse gas

water vapor

convection currents stirring the atmosphere produce

winds

Light-colored objects reflect more light than dark-colored ones. true or false?

true

Newton's law of cooling also holds for heating. true or false?

true

order the different types of radiant energy from longest to shortest wavelength by placing a number from 1 to 7 beside each other

1 - radio waves 2 - microwaves 3 - infrared radiation 4 - visible light 5 - ultraviolet radiation 6 - X - rays 7 - gamma rays

on a sunny day, Earth's surface is a net __, and at night it is a net __

1. absorber 2. emitter

an object in thermal equilibrium is both __ and __ energy at the same rate

1. absorbing 2. radiating

air is transparent to both infrared (long) waves and visible (short) waves, unless the air contains excess __ and __

1. carbon dioxide 2. water vapor

type of radiant energy you feel as heat if you sit near a fireplace 1. infrared radiation 2. microwaves 3. ultraviolet 4. x-rays

1. infrared radiation

Glass is __ to visible light waves, but __ infrared waves

1. transparent 2. absorbs

__ is the gas most rapidly increasing in the atmosphere

CO2

use the figure above to explain Earth's global warming

Earth's atmosphere allows short waves from the sun to pass through. These waves strike Earth, which re-radiates the energy as longer waves. Atmospheric gases absorb and re-emit much of this long-wavelength radiation back to Earth

Explain, the two ways convection currents produced by uneven heating of Earth's surface produce sea breezes

a. during the day: the shore warms more easily than the water. Air over the shore rises, and cooler air from above the water takes its place, producing a breeze toward the land b. at night: the shore cools off more quickly than the water. Air over the water rises, and the cooler air from above the shore takes it place, producing a breeze toward the sea.

How do birds vary their insulation

by fluffing their feathers to create air spaces

I for insulator wood - i straw - i air - i cork - i wool - i paper - i polystyrene - i

c for conductor aluminum - conductor silver - c iron - c copper - c

record-breaking cold nights occur when the skies are

clear

In conduction, __ between particles transfer thermal energy

collisions

why can't energy move from the sun to Earth by conduction or convection?

conduction is the transfer of heat from molecule to molecule, and the convection is the transfer of heat by expansion and rising of matter. Both of these are impossible in space because there is almost no matter

what is a conductor

conductor is a material that conducts heat well

an object hotter than its surroundings eventually __ to match the surrounding temperature

cools

a good. absorber of radiant energy appears __

dark

in expanding air, the average speed of the molecules __ and the air cools

decreases

radiation is energy transmitted by

electromagnetic waves

define radiant energy

energy that is transmitted by radiation

all substances continuously emit only one specific wavelength of radiant energy. true or false?

false

as air rises, it expands because more atmospheric pressure squeezes on it at higher altitudes. true or false?

false

both heat and cold are forms of energy. true or false?

false

materials that are good conductors of heat are usually poor conductors of heat are usually poor conductors of electricity. true or false?

false

the average __ of radiant energy is directly proportional to the Kelvin temperature of the emitter

frequency

in convection, heat is transferred by movement of the __ substance from one place to another

hotter

the part of radiant energy that is absorbed by objects increases the __ energy of the objects

internal

you notice that a blacktop pavement becomes hotter than other nearby surfaces on a hot day. What will you notice about the temperature of the blacktop pavement at night

it will cool faster than other surfaces

order the star colors white, red, and blue from coolest to hottest

red, white, blue

explain why the inside of a car becomes so much hotter than its surroundings on a hot day

short wavelengths from the sun can pass through the car's glass and into the car, warming the car. The car radiates longer wavelengths that cannot pass out through the glass. The energy is trapped inside the car

explain why snow is sometimes used to construct dwellings in cold climates

snowflakes imprison a lot of air in their crystals and are good insulators. the snow prevents heat from escaping too rapidly

the radiant energy emitted by stars is called

stellar radiation

an infrared thermometer measures the infrared radiant energy emitted by a body and converts it to

temperature

the __ of an object doesn't change if it is in thermal equilibrium

temperature

the radiant energy emitted by Earth is called

terrestrial radiation

suppose a heater is placed near the floor of a room. Describe the steps in which convection currents keep the air stirred up in the room

the heater warms nearby air, and the warm air rises. Cooler air near the ceiling moves downward, and the heater warms it. This air then rises, and the process continues.

a figure shows ice at the bottom of a test tube and boiling water at the top. Explain why the heat that boils the water doesn't melt the ice

the hot water a the top of the tube is less dense and floats. Any heat that reaches the ice must be transferred by conduction, but water is a poor conductor of heat

state Newton's law of cooling

the rate of cooling of an object is approximately proportional to the temperature difference between the object and its surroundings

a hot apple pie will cool faster in a freezer than on a kitchen table because __

the temperature difference is greater

define conduction

the transfer of energy within materials and between different materials that are in direct contact

what is the greenhouse effect?

the warming of a planet's surface due to the trapping of radiation by the planet's atmosphere