Unit 3 & 8

Question 1

Temperature

Answer 1

a measure of the average random kinetic energy of the particles in a substance.

Question 2

Specific Latent Heat of Fusion/Vaporization

Answer 2

the energy required to change the phase of 1kg of a substance from a solid/liquid to a liquid/gas without any temperature change.

Question 3

Specific Heat Capacity

Answer 3

the energy required to heat 1kg of a substance by 1K.

Question 4

Internal Energy

Answer 4

the total of the potential energy and the random kinetic energy of all the particles in the substance.

Question 5

Absolute temperature

Answer 5

a temperature measured from absolute zero in kelvins.

Question 6

Ideal Gas

Answer 6

a hypothetical gas whose molecules occupy negligible space and have no interactions, and which consequently obeys the gas laws exactly.

Question 7

Boyle’s Law

Answer 7

for a fixed mass of gas at constant temperature the pressure is inversely proportional to the volume.

Question 8

Charles’ Law

Answer 8

for a fixed mass of gas at constant pressure the volume is directly proportional to the absolute temperature.

Question 9

Pressure Law

Answer 9

for a gas of fixed mass and volume, the pressure is directly proportional to the absolute temperature.

Question 10

Mole

Answer 10

the number of molecules in 12g of carbon 12.

Question 11

Molar Mass

Answer 11

the mass of a substance divided by the number of molecules.

Question 12

Thermal Energy

Answer 12

the net amount of energy transferred between two bodies at different temperatures.

Question 13

Pressure

Answer 13

force per unit area

Question 14

Specific Energy

Answer 14

The energy released per unit mass of a fuel.

Question 15

Energy Density

Answer 15

The energy released per unit volume of a fuel.

Question 16

Primary Energy Source

Answer 16

a source of energy that has not been transformed or converted before use by the consumer.
uranium 235, crude oil, coal, sun, water, wind etc.

Question 17

Secondary Energy Source

Answer 17

an energy source created using a primary source eg electricity.

Question 18

Renewable Energy

Answer 18

energy generated from renewable resources, which are naturally replenished on a human timescale.
sunlight, wind, rain, tides, waves, and geothermal heat.

Question 19

Conduction

Answer 19

the transfer of heat by collisions of particles and movement of electrons within a body

Question 20

Convection

Answer 20

the movement of groups of atoms or molecules within fluids that arises through variations in density.

Question 21

Thermal Radiation

Answer 21

The transfer of energy by means of electromagnetic radiation.

Question 22

Black body

Answer 22

A hypothetical body that absorbs and emits all radiation that falls on it.

Question 23

Intensity

Answer 23

Power emitted per square meter.

Question 24

Albedo

Answer 24

The ratio of scattered radiation from the surface to incident radiation upon it.

Question 25

Solar Constant

Answer 25

The mean solar intensity of EM radiation that would be incident on a plane perpendicular to the rays, at a distance of one AU from the Sun. SC = 1400 Wm^-2

Question 26

Degradation of Energy

Answer 26

In any natural process, some energy becomes unavailable to do useful work.

Question 27

Wien’s Displacement Law

Answer 27

The black body radiation curve for different temperatures peaks at a wavelength inversely proportional to the temperature

Question 28

Stefan-Boltzmann Law

Answer 28

The radiated power from a black-body radiator is directly proportional to the fourth power of the black body’s surface temperature.

Question 29

Emissivity

Answer 29

The ratio of energy/power emitted (per unit area) of a body to the energy/power emitted (per unit area) of a black body of the same dimensions and the same temperature.