Waves

Question 0

Why does the direction the wave is travelling tell you about the direction the energy is going

Answer 0

The direction of travel of the wave is the direction at which the wave transfers energy

Question 1

What are waves used to transfer

Answer 1

Energy and information

Question 2

What are the two types of wave

Answer 2

Transverse and longitudinal

Question 3

What is the direction of energy transfer for a transverse wave

Answer 3

Perpendicular to the direction at which the wave travels

Question 4

What direction does a longitudinal wave travel

Answer 4

Parallel to the direction of energy transfer

Question 5

What is a longitudinal wave made up off

Answer 5

Compression and rarefactions

Question 6

Give an example of a mechanical wave

Answer 6

Waves on springs

Question 7

How do mechanical waves travel

Answer 7

As transverse or longitudinal waves

Question 8

Why are all electromagnetic waves transverse waves

Answer 8

Because there are no moving particles in a electromagnetic wave, so the oscillations are perpendicular to the direction of travel.

Question 9

What kind of wave are sound waves

Answer 9

Longitudinal

Question 10

What type of wave can be produced on a piece of stretched spring

Answer 10

Transverse, mechanical waves

Question 11

What is the amplitude of a wave

Answer 11

The distance between the height of the wavelength (peak) and the position at rest

Question 12

In terms of energy, what does increasing the amplitude mean

Answer 12

It increases the amount of energy a wave carries

Question 13

What is the wavelength of a wave

Answer 13

The distance for one crest to the next crest, or from one trough to the next

Question 14

What is the frequency of a wave

Answer 14

The number of wave crests passing a point in one second

Question 15

What is the unit for frequency

Answer 15

Hertz, Hz

Question 16

What is the wavelength for a longitudinal wave

Answer 16

The distance from the middle of one compression to the middle of the next compression

Question 17

How do you tell the frequency of longitudinal waves

Answer 17

The number of compressions passing a certain point in one second

Question 18

Why is an image seen in a mirror

Answer 18

Because of the reflection of light

Question 19

What is the “normal”

Answer 19

Straight line through a surface or boundary perpendicular to the surface boundary

Question 20

In reflection the angle of incidence should be equal to

Answer 20

The angle of reflection

Question 21

Describe the image formed in a mirror

Answer 21

• the same size as the object
• upright
• the same distance behind the mirror as the object is in front
• virtual

Question 22

What is a real image

Answer 22

An image that can be formed on a screen because rays of light that produce the image can actually pass through it

Question 23

What is a virtual image

Answer 23

It can be formed on a screen because the rays of light that produce the image only appear to pass through it

Question 24

What happens to light waves when they cross a boundary

Answer 24

They speed up, the wavelength changes but the frequency stays the same

Question 25

When does light refract

Answer 25

When it crosses a boundary such as air or water

Question 26

Can all waves diffract

Answer 26

Yes

Question 27

What causes waves to change direction during refraction

Answer 27

The change in speed

Question 28

What happens to the speed of the wave when it enters a more dense object

Answer 28

It slows down and the ray changes direction towards the normal

Question 29

What happen when light enters a less dense object

Answer 29

It speeds up and moves away from the normal

Question 30

When will a wave not change direction

Answer 30

If it is travelling along the normal

Question 31

Why does refraction take place

Answer 31

When light crosses a boundary

Question 32

Which light is refracted the most

Answer 32

Violet light

Question 33

Which light spectra is least refracted

Answer 33

Red light

Question 34

Why does light split up into different colours when it passes through a triangular prism

Answer 34

Because different wavelengths of light are refracted by different amounts

Question 35

What is diffraction

Answer 35

The spreading of waves when they pass through a gap or round an obstacle

Question 36

Why don't we see the diffraction of light in everyday life

Answer 36

Because the wavelength of light is too small

Question 37

What kind of signals are carried by radio waves

Answer 37

TV signals

Question 38

Why may people in hilly areas not be able to receive TV signals

Answer 38

Because the signal gets blocked by a hill

Question 39

What sort of waves are diffracted

Answer 39

All types of waves are diffracted

Question 40

What is sound caused by

Answer 40

Mechanical vibrations in a substance

Question 41

In what state does sound travel through best

Answer 41

Solids

Question 42

In which state does sound travel slowest

Answer 42

Gases

Question 43

What is the range of human hearing

Answer 43

20Hz- 20,000Hz

Question 44

What is a reflected sound wave called

Answer 44

Echoes

Question 45

What sort of surfaces reflect sound

Answer 45

Hard, flat surfaces such as walls or floors

Question 46

What sort of surfaces absorb sound

Answer 46

Soft furniture: carpets, curtains and furniture

Question 47

Where does refraction take place

Answer 47

At the boundaries between layers of air at different temperatures

Question 48

What does the pitch of a note depend on

Answer 48

The frequency of the sound waves

Question 49

What effect does increasing the frequency have

Answer 49

The higher the pitch

Question 50

What does the loudness of an instrument depend on

Answer 50

The amplitude of the sound waves

Question 51

Why does increasing the amplitude have this effect on sound

Answer 51

Because the greater the amplitude, the more energy the wave carries and the louder the sound

Question 52

What piece of equipment shows waves

Answer 52

An oscilloscope

Question 53

Why do different instruments sound different when they play the same note

Answer 53

The waveforms are different

Question 54

What produces a pure sound

Answer 54

Tuning fork and signal generators

Question 55

What controls the quality of an instrument

Answer 55

The waveform

Question 56

How does a flute make sound

Answer 56

The air in the pipe vibrates as you blow onto the mouthpiece