Chapter 5 Physical Science

The physics of a refrigerator most closely resembles the physics of

a heat engine

A person stands on a very sensitive scale and inhales deeply. The reading on the scale

any of the above, depending

Molecular motion is not responsible for

buoyancy

The working substance (or refrigerant) used in most refrigerators is a

gas that is easy liquefy

At constant pressure, the volume of a gas sample is directly proportional to

its absolute temperature

On the molecular level, heat is

kinetic energy

The volume of a gas sample is increased while its temperature is held constant. The gas exerts a lower pressure on the walls of its container because its molecules strike on the walls

less often

absolute zero may be regarded as that temperature at which

molecular motion in a gas would be the minimum

A refrigerator gives off

more heat than it absorbs from its contents

Heat transfer in a vacuum can occur by

radiation only

Heat transfer in a gas can occur by

radiation, convection, conduction

The pressure of the earth's atmosphere at sea level is due to

the gravitational attraction of the earth for the atmosphere

Food cooks more rapidly in a pressure cooker than in an ordinary pot with a loose lid because

the high pressure raises the boiling point of water

The greater the entropy of a system of particles,

the less the order of the system

At a given temperature

the molecules in a gas all have the same average energy

When evaporation occurs, the liquid that remains is cooler because

the slowest molecules remain behind

The fluid at the bottom of a container is

under more pressure than the fluid at the top

heat is absorbed by the refrigerant in a refrigerator when it

vaporizes