thermal physics

Question 1

conservation of energy law

Answer 1

the energy transferred to an object when work is done on it is always equal in size to the amount of energy lost by the second object that is doing work(energy can not be created or destroyed)

Question 2

Efficiency

Answer 2

a measure of how much input energy is converted into useful output energy

Question 3

heat

Answer 3

a quantity of thermal energy transferred

Question 4

temperature

Answer 4

a quantity that measures the average kinetic energy of particles

Question 5

specific heat capacity

Answer 5

the specific heat capacity is the required to increase the temperature of 1kg of a substance by 1K

Question 6

latent heat of fusion

Answer 6

the energy required to change state of 1kg of a substance. used to state changes of states between liquids and solids

Question 7

latent heat of vaporisation

Answer 7

the energy required to change state of 1kg of a substance. this is used to state changes of states between liquids and gases

Question 8

ideal gasses

Answer 8

a gas where all the collisions between particles are elastic, the particles exert no forces on one another, and it is assumed that particles take up no space.

Question 9

internal energy

Answer 9

the sum of the kinetic energy and potential energy stored within a substance

Question 10

0th law of thermodynamics

Answer 10

when two systems are in thermal contact, but there is no net transfer of heat because they are at the same temperature.

Question 11

1st law of thermodynamics

Answer 11

the change in internal energy of a system is equal to the heat energy input minus the output work done

Question 12

2nd law of thermodynamics

Answer 12

heat will not flow from a colder body into a hotter one without the input of work

Question 13

heat engine

Answer 13

machines designed to convert thermal energy into useful mechanical work

Question 14

compression

Answer 14

where the volume of a fluid is decreased

Question 15

expansion

Answer 15

where the volume of a fluid is increased

Question 16

adiabatic process

Answer 16

where work is done but there is no heat transfer

Question 17

isothermal process

Answer 17

heat transfer that takes place at a constant temperature

Question 18

refrigerator

Answer 18

a heat pump that transfers heat away from the cooler reservoir to the hot reservoir (to intentionally make the region colder

Question 19

heat pump

Answer 19

a device that applies external work to extract heat from a cold reservoir and transfer it to a hot region

Question 20

maximum theoretical efficiency

Answer 20

no real engine can achieve a thermal efficiency higher than that of an ideal reversible engine operating between the same temperatures