CP4

Question 1

What are waves?

Answer 1

A way of transferring energy or information without transferring matter. Many waves travel when particles pass on vibrations.

Question 2

What are the two types of waves?

Answer 2

1. Transverse waves
2. Longitudinal waves

Question 3

What are transverse waves?

Answer 3

A wave where the vibrations are at right angles to the direction in which the wave is travelling.

Question 4

What are longitudinal waves?

Answer 4

A wave where the vibrations are parallel to the direction in which the wave is travelling (this can be shown with a slinky moving parallel)

Question 5

What is Wave Frequency?

Answer 5

The number of waves passing a point each second.

Question 6

What are some examples of transverse waves?

Answer 6

1. Light waves
2. Ultraviolet radiation
3. Water waves
4. S waves (Earthquakes)

Question 7

What are some examples of longitudinal waves?

Answer 7

1. Sound waves
2. Ultrasound waves
3. P waves (Earthquake)

Question 8

What is Wave Frequency measured in?

Answer 8

Hertz (Hz).

Question 9

What is a period on a wave?

Answer 9

The length of time it takes one wave to pass a given point.

Question 10

Where is wavelength measured from in a longitudinal wave?

Answer 10

It is measured from one compression to another compression.

Question 11

What is the symbol for wave length?

Answer 11

Lambda (λ)

Question 12

What is the wavelength of a wave?

Answer 12

It is the distance from a point on one wave to a point in the same position on the next wave. It is measured in metres (m).

Question 13

What is the amplitude of a wave?

Answer 13

The maximum distance of a point on the wave way from its rest position (it is measured from the middle line of the wave to the top most point on a wave), the greater the amplitude of a sound wave, the louder the sound.

Question 14

What is the trough on a wave?

Answer 14

It is the bottom most point of a wave.

Question 15

What is the crest on a wave?

Answer 15

It is the top most point of a wave.

Question 16

What is the equation for wave speed (involving distance and time)?

Answer 16

Wave speed(m/s)=distance(m)/time(s)

Question 17

What is the equation for wave speed (involving frequency and wave length)?

Answer 17

Wave speed(m/s)=frequency(Hz) x Wavelength(m)

Question 18

What does the speed of a wave always depend on?

Answer 18

It always depends on the medium that the wave is travelling through. Light travels slower in glass and water than in a vaccum.

Question 19

What are the units for the equation for wave speed (involving frequency and wavelength)?

Answer 19

v= f x λ (v=speed, f=wave frequency, λ=wavelength)

Question 20

What is the formula triangle for the equation for wave speed (involving frequency and wave length)?

Answer 20

Wave speed
Frequency | Wavelength

Question 21

What is the speed of light in a vacuum?

Answer 21

300,000,000m/s

Question 22

What happens to the wavelength of light when going from air to water?

Answer 22

The wavelength reduces.

Question 23

How can you measure the speed of sound?

Answer 23

By measuring the time it takes for a sound to travel in a certain distance (e.g. standing in front of a large wall and measuring how long it takes for the echo sound to reach you), then because you have the time taken and the distance between you and the wall, you can use the distance time equation to work out the speed.

Question 24

How can you measure the speed of waves in water?

Answer 24

By measuring the time it takes for a wave to travel between two fixed points such as buoys. The speed can be calculated from the time and distance between the points.

Question 25

What is refraction?

Answer 25

The change in direction when a wave goes from one transparent material to another.

Question 26

What direction does light refract when going from air to glass/water?

Answer 26

Towards the normal.

Question 27

What direction does light refract when going from glass/water to air?

Answer 27

Away from the normal.

Question 28

What is the normal line in refraction?

Answer 28

An imaginary line drawn at right angles to the surface of a mirror or lens where a ray of light hits it.

Question 28

What direction does light travelling along the normal line go towards when going into a different medium?

Answer 28

Light travelling along the normal line does not change direction when going into a different medium.

Question 29

Why do objects seem closer than they really are in water?

Answer 29

As light reflected by it changes direction when it leaves the water.

Question 30

Does light travel faster in air or glass/water?

Answer 30

Light travels faster in air.

Question 31

What happens to the speed of the light as it changes between one medium and another?

Answer 31

As light passes from one medium to another, it changes speed which causes the direction of the light to change.

Question 32

What does the bend of the refraction depend on?

Answer 32

It depends on how fast the light travels in the two media and the angle of the light hitting the interface. The greater the difference in speed between the two media, the more the light is bent.

Question 33

When does light bend towards the normal?

Answer 33

When light slows down.

Question 34

When does light bend away from the normal?

Answer 34

When light speeds up.

Question 35

How does the depth of water affect the speed of waves in water?

Answer 35

Waves moving from deep water into shallow water slow down and change direction to move towards the normal. Waves moving from shallow to deep water speed up and change direction to move away from the normal.