Waves Definitions

Question 1

Frequency

Answer 1

the number of waves passing any point per second

Question 2

Period

Answer 2

the time for one oscillation

Question 3

Wavelength

Answer 3

the distance between any point on a wave and the equivalent point on the next

Question 4

Amplitude

Answer 4

the maximum distance a point moves from its rest position when a wave passes

Question 5

Ultrasound

Answer 5

sound with a frequency of higher than 20kHz(above the range of human hearing)

Question 6

Compression

Answer 6

a region in a longitudinal wave with a higher than normal pressure(particles are closer together)

Question 7

Rarefaction

Answer 7

a region in a longitudinal wave with a lower than normal pressure(particles are further apart)

Question 8

Echo

Answer 8

a reflection of sound waves

Question 9

Luminous

Answer 9

capable of emitting their own light

Question 10

Non-luminous

Answer 10

incapable of emitting their own light

Question 11

Diffuse reflection

Answer 11

the reflection of light from an uneven surface such that an incident ray is reflected at many angles rather than just one

Question 12

Regular reflection

Answer 12

the reflection of light from a smooth surface such that an incident ray is reflected entirely within the same angle

Question 13

Monochromatic

Answer 13

referring to light of a single frequency, wavelength and colour

Question 14

Angle of incidence

Answer 14

the angle between the incident ray and the normal

Question 15

Angle of refraction

Answer 15

the angle between the refracted ray and the normal

Question 16

Real image

Answer 16

an image formed when rays from a source focus(meet) to form it

Question 17

Virtual image

Answer 17

an image formed by the imaginary intersection of light rays

Question 18

Angle of refraction

Answer 18

the angle between the refracted ray and the normal

Question 19

Refractive index

Answer 19

the ratio of speeds of a wave in two different regions

Question 20

Dispersion

Answer 20

the separation of white light into colours according to wavelength

Question 21

Critical angle

Answer 21

the angle of incidence beyond which total reflection occurs

Question 22

Principal focus

Answer 22

the point where rays converge(meet)

Question 23

Focal length

Answer 23

the distance from the centre of the lens to the principal focus

Question 24

Principal axis

Answer 24

a line which passes through the centre of the lens