3. Transverse and Longitudinal Waves

Question 1

What is a transverse wave?

Answer 1

Waves in which the direction of vibration of the particles is perpendicular to the direction of energy propagation (transfer)

Question 2

Name 4 transverse waves

Answer 2

1. The EM waves
2. Ripples on water
3. Waves on strings
4. Some types of earthquake shock waves (S-waves)

Question 3

What are the 2 main ways of representing a transverse wave?

Answer 3

1. Graph of displacement against distance along the path of the wave
2. Graph of displacement against time for a point as the wave passes

Question 4

What does the distance between 2 adjacent points on the displacement against distance give?

Answer 4

The wavelength

Question 5

What does the distance between 2 adjacent points on the displacement against time give?

Answer 5

The period

Question 6

What is a longitudinal wave?

Answer 6

Waves in which the direction of vibration of the particles is parallel to the direction of energy propagation (transfer)

Question 7

Name 3 longitudinal waves

Answer 7

1. Sound
2. Some types of earthquake shock waves (P-waves)
3. Compression waves (slinky)

Question 8

What is the main way of representing a longitudinal wave?

Answer 8

Graph of displacement against time (looks like a transverse wave but isn’t…)

Question 9

Define the term polarised wave

Answer 9

A wave that oscillates in one direction only

Question 10

What type of wave cannot be polarised

Answer 10

Longitudinal waves

Question 11

What happens when light is shone at two polarising filters at right angles to each other?

Answer 11

No light will get through

Question 12

What does the polarisation of transverse wave provide evidence for?

Answer 12

The nature of transverse waves

Question 13

What happens when light is shone at two polarising filters through 90 degrees to each other?

Answer 13

The intensity of the polarised light will decrease because some light can get through

Question 14

How did Young explain how light could be polarised?

Answer 14

1. Light was a transverse wave

2. Consist of vibrating electric and magnetic fields perpendicular to the direction of energy transfer

Question 15

What are the 2 main uses of polarisation in the real world?

Answer 15

1. Glare reduction in photography and Polaroid sunglasses
2. Improving TV and radio signals where the rods of the receiving aerial needs to line up with the transmitting aerial for a strong signal