Waves part 1

Question 1

Longitudinal waves?

Answer 1

A longitudinal wave is one in which the particles vibrate parallel to the direction in which the wave is travelling. The only types of longitudinal waves relevant to your GCSE course are:

1. Sound waves.
2. Ultrasound waves.
3. Slinky spring waves.
4. P-type earthquake waves.

Question 2

Explain how a longitudinal wave moves along a slinky spring?

Answer 2

Waves move parallel to the axis of the stretched spring. Compressions are places where the coils (or particles) bunch together. Rarefactions are places where the coils (or particles) are furthest apart. All longitudinal waves are made up of compressions and rarefactions.

Question 3

What is a transverse waves?

Answer 3

A transverse wave is one in which the vibrations are at 90o to the direction in which the wave is travelling. Examples:

1. Water waves
2. Slinky spring waves
3. Waves on strings and ropes
4. Electromagnetic waves

Question 4

What do waves transfer? How are they produced? And what can they be classified as?

Answer 4

Waves transfer energy from one point to another. All waves are produced as a result of vibrations and can be classified as longitudinal or transverse.

Question 5

What is frequency?

Answer 5

Frequency is the number of complete waves passing a fixed point in a second

Question 6

What is wave length?

Answer 6

Wavelength is the distance between two consecutive crests or troughs.

Question 7

What is amplitude and double amplitude?

Answer 7

Amplitude is the greatest displacement of the wave from its undisturbed position.
2A/ double amplitude is just amplitude doubled.

Question 8

What is the wave equation?

Answer 8

Wave speed = frequency x wavelength

Wavelength= symbol- λ
Frequency= (hertz) symbol- f

Question 9

What is the equation for frequency?

Answer 9

Frequency= 1/T = Answer

Question 10

What is reflection?

Answer 10

Reflection is sending back a wave into the medium from which it came.

Question 11

How do you draw a ray of incidence and reflection?

Answer 11

1. The angle of incidence always equals the angle of reflection
2. The wavelengths of incident and reflected waves are equal.
3. The frequency of the incident waves is the same as that of the reflected waves.
4. There is continuity of incident waves and reflected waves at the barrier.

Question 12

What is refraction?

Answer 12

Refraction is the change in direction of a wave passing from one medium to another caused by its change in speed.

Question 13

What happens when waves pass from deep to shallow water?

Answer 13

1. The angle of incidence in deep water is always bigger than the angle of refraction in shallow water.
2. The wavelength and speed of waves in deep water are greater than those in shallow water.
3. The frequencies of waves in both deep and shallow water are the same.
4. There is continuity of incident and refracted waves at the boundary.

Question 14

What happens when water waves reflect compared to when they pass from deep into shallow water?

Answer 14

When they reflect:

1. Angle of incidence = angle of reflection
2. Reflected wavelength = incidence wavelength
3. Reflected frequency = incidence frequency
4. Reflected speed = incident speed

When they pass from deep into shallow water:

1. They bend towards the normal
2. Refracted wavelength is less than incident wavelength
3. Refracted frequency = incident frequency
4. Refracted speed is less than incident speed.

Question 15

What happens when light reflect compared to when they pass from air into glass and It refracts?

Answer 15

When it reflects:

1. Angle of incidence = angle of reflection
2. Reflected wavelength = incidence wavelength
3. Reflected frequency = incidence frequency
4. Reflected speed = incident speed

When they pass from deep into shallow water:

1. They bend towards the normal
2. Refracted wavelength is less than incident wavelength
3. Refracted frequency = incident frequency
4. Refracted speed is less than incident speed.