Topic 4 - Waves

Question 1

Waves definition

Answer 1

A transfer of energy without transferring matter

Question 2

What is wavelength?

Answer 2

Length of one wave from peak to peak. Measured in metres

Question 3

What is amplitude?

Answer 3

Maximum displacement of a particle from its rest position. Measure in metres.

Question 4

What is wave velocity?

Answer 4

Speed of a wave. (m/s)

Question 5

What is time period?

Answer 5

Time it takes for 1 wave to pass a stationary point. (s)

Question 6

What is frequency?

Answer 6

Number of whole waves passing a stationary point each second. (Hz)

Question 7

What happens in a transverse wave?

Answer 7

Particles oscillate perpendicular to the direction of wave travel. (Light, water, all of the EM spectrum)

Question 8

What happens in a longitudinal wave?

Answer 8

Particles oscillate parallel to the direction of wave travel (sound).

Question 9

Equation for wave velocity

Answer 9

Wave speed (m/s) = frequency (Hz) x wavelength (m) 
V = f×λ

Question 10

Equation for wave speed

Answer 10

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

Question 11

Law of refraction

Answer 11

The angle of incidence = the angle of reflection

Question 12

Refraction

Answer 12

A wave changes direction when it crosses a boundary because it changes speed. If it enters a denser medium it slows down and bends towards the normal.