4 Properties of Waves

Question 1

Waves transfer ______ without transferring ______

Answer 1

energy, matter

Question 2

Describe wave motion

Answer 2

Illustrated by vibration in ropes and springs, and experiments using water waves

Question 3

Understand the term wavefront

Answer 3

wavefronts are imaginary surfaces through crests, perpendicular to the direction of energy propagation of the wave

Question 4

Understand the term ray

Answer 4

The ray is a mathematical line perpendicular to the wavefront, giving the direction of energy transfer of the wave

Question 5

State the meaning of the speed of a wave

Answer 5

how fast the wave is traveling

Question 6

State the meaning of the frequency of a wave

Answer 6

the number of peaks or troughs that pass a certain point each second, or the number of cycles completed in a second

Question 7

State the meaning of the wavelength of a wave

Answer 7

the distance between two consecutive compressions or rarefactions
the distance between two successive crests or troughs

Question 8

State the meaning of the amplitude of a wave

Answer 8

the difference between a crest or a trough and the equilibrium

Question 9

State the meaning of a node in a wave

Answer 9

where the wave crosses the equilibrium

Question 10

State the meaning of the equilibrium of a wave

Answer 10

the midline of the wave, the medium of the wave’s resting position

Question 11

State the meaning of the crest of a wave

Answer 11

the highest point on a wave

Question 12

State the meaning of the trough of a wave

Answer 12

the lowest point on a wave

Question 12

State the meaning of the trough of a wave

Answer 12

the lowest point on a wave

Question 13

Define a wave

Answer 13

an oscillation or vibration accompanied by a transfer of energy that travels through space or mass

Question 14

Define a medium

Answer 14

an intervening substance through which a wave can transfer its energy

Question 15

Transverse wave

Answer 15

a wave vibrating perpendicular to the direction of travel in a sine curve shape

Question 16

Longitudinal wave

Answer 16

a wave vibrating in the same direction it is traveling

Question 17

State the meaning of a compression of a wave

Answer 17

a region in a longitudinal wave where the particles are closest together

Question 18

State the meaning of a rarefaction of a wave

Answer 18

a region in a longitudinal wave where the particles are furthest apart

Question 19

Examples of transverse waves

Answer 19

light, water

Question 20

Example of longitudinal waves

Answer 20

sound

Question 20

Example of longitudinal waves

Answer 20

sound

Question 21

Characteristics of electromagnetic and mechanical waves

Answer 21

electromagnetic - oscillating electric/magnetic fields
mechanical - oscillating particles

Question 22

Units for frequency of a wave

Answer 22

Hertz (Hz)
1Hz = 1/s

Question 23

Equation relating wavelength, frequency and speed of a wave

Answer 23

v = fλ speed of wave = frequency x wavelength m/s = Hz x m

Question 24

The denser the medium, the ______ the mechanical wave travels and the ______ the electromagnetic wave travels

Answer 24

faster, slower

Question 25

Pitch

Answer 25

High: waves close together / high frequency Low: waves further apart / lower frequency

Question 25

Pitch

Answer 25

High: waves close together / high frequency Low: waves further apart / lower frequency

Question 26

Loud sounds = Quiet sounds =

Answer 26

high amplitude low amplitude

Question 27

Humans can detect frequencies between ...

Answer 27

20Hz and 20,000Hz

Question 28

Diffraction

Answer 28

when waves travel through a narrow gap of width approximately equal to their wavelength, the waves diffract - diffracting waves widen after travelling through the gap

Question 29

Echo formula

Answer 29

speed = distance / time where distance = x2

Question 30

No sound in vacuum because ...

Answer 30

No particles to transfer the energy

Question 31

An electromagnetic field is the ___________ of an ___________ electric field

Answer 31

propagation, oscillating

Question 32

Electromagnetic waves are all __________ waves

Answer 32

transverse

Question 33

Electromagnetic spectrum order

Answer 33

radio waves, microwaves, infra-red, visible light, ultraviolet, x-rays, gamma rays

Question 34

Electromagnetic spectrum order: does frequency increase or decrease along it?

Answer 34

increases

Question 35

Electromagnetic spectrum order: does wavelength increase or decrease along it?

Answer 35

decreases

Question 36

For light, wavelength and frequency are ...

Answer 36

inversely related

Question 37

Properties of reflected images (6)

Answer 37

right way up, same size, same colour, virtual, same distance, laterally centred

Question 38

Formula for refractive index

Answer 38

n = sin(i) / sin(r)

Question 39

Speed of electromagnetic waves in a vacuum

Answer 39

3 x 10⁸ m/s