Energy

Question 1

law of conservation of energy

Answer 1

a law that states that energy cannot be made or lost. However, energy can be transformed from one type to another or transferred from one object to another.

Question 2

electrical energy

Answer 2

the energy made available by the flow of electric charge through a conductor

Question 3

gravitational potential energy

Answer 3

energy stored due to the height of an object above a base level

Question 4

nuclear energy

Answer 4

the energy stored at the centre of atoms, the tiny particles that make up all substances. Nuclear energy can be released from the radioactive metals uranium or plutonium, and transformed into electrical energy in a nuclear power station.

Question 5

efficiency

Answer 5

the fraction of energy supplied to a device as useful energy. It is usually expressed as a percentage.

Question 6

conduction

Answer 6

transfering heat through collisions between particles

Question 7

insulators

Answer 7

a material that is a poor conductor of heat

Question 8

convection

Answer 8

transfer of heat through the flow of particles

Question 9

radiation

Answer 9

a method of heat transfer that does not require particles to transfer heat from one place to another

Question 10

radiant heat

Answer 10

heat transferred by radiation, as from the sun to the Earth

Question 11

reflected

Answer 11

bounced off

Question 12

transmitted

Answer 12

passed through something, like light or sound passing through air

Question 13

absorbed

Answer 13

for something to be taken in

Question 14

density

Answer 14

the degree of compactness of a substance

Question 15

luminous

Answer 15

releasing its own light

Question 16

incandescent

Answer 16

describes objects that emit light when they are hot

Question 17

bioluminescent

Answer 17

describes living things that release light energy

Question 18

non-luminous

Answer 18

describes objects that do not emit their own light, but can be seen by reflected light

Question 19

scattered

Answer 19

describes light sent in many directions by small particles within a substance

Question 20

visible spectrum

Answer 20

different colours that combine to make up white light; they are separated in rainbows

Question 21

dispersion

Answer 21

separation of the colours that make up white light. Each colour is bent differently when it enters or leaves a glass prism.

Question 22

electromagnet radiation

Answer 22

the radiant energy such as radio waves, infrared, visible light, X-rays and gamma rays released by magnetic or electric fields

Question 23

electromagnet spectrum

Answer 23

complete range of wavelengths of energy radiated as electric and magnetic fields

Question 24

radio waves

Answer 24

low energy electromagnetic waves with a much lower frequency and longer wavelength than visible light

Question 25

infra-red radiation

Answer 25

low energy electromagnetic waves with a much lower frequency and longer wavelength than visible light

Question 26

X-ray

Answer 26

high energy electromagnetic waves that can be transmitted through solids and provide information about their structure

Question 27

gamma rays

Answer 27

high energy electromagnetic radiation produced during nuclear reaction

Question 28

elastic potential energy

Answer 28

Elastic energy is the potential mechanical energy stored in the configuration of a material or physical system

Question 29

pitch

Answer 29

the quality of a sound governed by the rate of vibrations producing it; the degree of highness or lowness of a tone.

Question 30

rarefration

Answer 30

being deflected in passing obliquely through the interface between one medium and another or through a medium of varying density

Question 31

decibels

Answer 31

a unit used to measure the intensity of a sound or the power level of an electrical signal by comparing it with a given level on a logarithmic scale.

Question 32

frequency

Answer 32

the rate at which something occurs over a particular period of time or in a given sample.