Physics Ch. 15-18 Test

Réussis tes devoirs et examens dès maintenant avec Quizwiz!

What is the temperature of freezing water in Celsius

0 C

the second law of thermodynamics makes it impossible to attain a temperature of...

0 K

entropy is closely related to the

2nd law of thermodynamics

The mechanical equivalent of heat in the SI system is...

4.18 J/cal

What is the difference between a calorie and a joule?

4.18j=1 cal

What is an example of radiation?

A black object radiates heat

How does a heat pump differ from a heat source?

A heat pump is a device that changes thermal energy into mechanical work. A heat source just has a greater temperature than its environment.

Example of conduction?

A pot sitting on a hot burner. A burning stove and my hand.

what is the third type of heat transfer?

Radiation

State the first law of thermodynamics

The change of internal energy of a closed system will be equal to the heat added to the system minus the work done by the system. (Energy cannot be created nor destroyed)

What is thermodynamics?

The study of processes in which energy is transferred as heat and as work.

What is internal energy?

The sum total of all the energy of all the molecules in a system.

state the law of entropy

The total entropy of any system plus that of its environment increases as a result of any natural process. Natural processes tend to move toward a state of greater disorder.

The molecules in a room-temperature glass of water jostle around at

a great variety of speeds

What is an ideal heat engine?

a heat engine in which each of the processes of heat addition and exhaust, of gas expansion or compression, were considered to be done reversibly

What is an isothermal process?

a process that occurs at constant temperature

second law of thermodynamics

heat flows from hot object to cold object, not the other way around

Increased air pressure on the surface of hot water tends to

prevent boiling

What is conduction?

Heat transfer within a material or between materials that are touching

Why does silver heat up more quickly than water?

It has a lower heat capacity

In the Joule experiment, no heat enters or leaves the insulating jar. The water-churning process is therefore an..... one

adiabatic

Why is condensation a warming process?

because the gas releases energy

When mechanical work is done on a system, there can be an increase in its

both temp and internal energy

The first law of thermodynamics is a special case of the...

conservation of energy

during an adiabatic expansion, the internal energy...

decreases

when the volume of a gas increases isothermally, its pressure... and its temperature remains...

decreases... constant

When the volume of a gas increases adiabatically, its pressure... and its temperature...

decreases... decreases

natural processes tend to increase... in the universe

entropy

Work done by a gas is considered positive when the gas.... and its temperature remains...

expands... decreases

the source of the heat equivalent of work done by an ideal gas during isothermal expansion is its... while the source of the heat equivalent of work done by an ideal gas during adiabatic expansion is its...

heat input at high temperature... internal energy of the gas

What is convection?

heat transfer in a fluid in which hot fluid rises and cold fluid sinks, setting up a cycle

Example of convection

hot air rising

When a volume of air is compressed, its temperature

increases

Suppose you put a closed, sealed can of air on a hot stove burner. The contained air will undergo an increase in

internal energy, temp, and pressure

What change in operating conditions increases the efficiency of an ideal heat engine?

lowering the lower operating temperature/raising the higher operating temperature

Systems that are left alone, tend to move toward a state of

more entropy

When heat is converted to another form of energy, or vice versa, there is... loss of energy

no

During an adiabatic compression of an ideal gas

no heat is supplied to or removed from the gas

What is an adiabatic process?

one in which no heat is allowed to flow into or out of the system

To totally convert a given amount of mechanical energy into heat is

possible

When a gas is changed to a liquid state, the gas

releases energy

During an isothermal expansion, the internal energy....

remains constant

Give an example of a heat pump

steam engine

Define specific heat

the heat required to raise the temperature of the unit mass of a given substance by a given amount

Evaporation is a cooling process because

the more energetic molecules are able to escape the liquid

Entropy is the amount of energy that cannot be converted into...

useful work

a temperature inversion occurs when the upper layers of air are

warmer than the lower regions of air


Ensembles d'études connexes

IGCSE Business Studies: Organisation & Management

View Set

Acute Upper & Lower Resp Disorder Unit

View Set

Western Civilization since 1500 (book) (20-29)

View Set

ME 251 Fundamentals of Metal Casting

View Set

Ch. 5 Volcanoes and Volcanic Hazards

View Set

CH 65 Assessment of Neurologic Function (E4)

View Set