Key Words

Question 0

Interface

Answer 0

Junction between two different materials

Question 1

Refraction

Answer 1

The change in speed and direction of a wave as it enters a new material

Question 2

Normal

Answer 2

Line at right angles to the surface of a mirror or lens where Ray of light hits it

Question 3

Converging or convex lens

Answer 3

A lens that is thicker in the middle than at its edges

Question 4

Spectrometer

Answer 4

An instrument that can split up light to show the colours of the spectrum

Question 5

Optical fibre

Answer 5

Glass or plastic strand which can direct light or infrared radiation

Question 6

Spectrum

Answer 6

The range of colours between red and violet obtained when white light is split up using a prism

Question 7

Red shift

Answer 7

Waves emitted by something moving away from an observer have their wavelength increased and frequency decreased compared to waves from a stationary object

Question 8

Epicentre

Answer 8

The point on the surface of the earth directly above the focus

Question 9

Focus

Answer 9

The point where an earthquake begins, usually under the surface

Question 10

Convection currents

Answer 10

Current caused by parts of a fluid being at a different temperature so a diferent density to the rest of the fluid

Question 11

Current

Answer 11

The rate of flow of charge

Question 12

Voltage

Answer 12

The measure of the amount of energy transferred by the current

Question 13

Earthquake

Answer 13

A sudden movement within the earth releasing a large amount of stored energy

Question 14

Efficiency

Answer 14

The proportion of input energy which has been transferred to a useful form

Question 15

Electricity

Answer 15

A flow of charged particles that can be used to transfer energy

Question 16

Frequency

Answer 16

The number of waves passing a point each second

Question 17

Fusion reaction

Answer 17

When the nuclei of two atoms join together and release energy

Question 18

Galaxy

Answer 18

A group of millions of stars held together by gravity

Question 19

Ionizing radiation

Answer 19

Radiation or certain types of high energy particles that can cause atoms to become electrically charged (to become ions)

Question 20

Reflecting telescope

Answer 20

A telescope in which the focussing of the main image is done by a curved mirror

Question 21

Vacuum

Answer 21

A place where there is no matter at all

Question 22

Wave speed

Answer 22

The distance that a wave travels in one second

Question 23

Wavelength

Answer 23

The distance between a point on one wave and the same point on the next wave

Question 24

Fluorescence

Answer 24

Absorbing radiation of one wavelength and re-emitting the energy at a different wavelength