Topic 4.5: Wave Properties

Question 1

Define Refraction

Answer 1

o REFRACTION: Change of direction at a boundary due to different wavespeed

Question 2

• 4.5.2: State and apply Snell’s law

Answer 2

SNELL’S LAW: For two particular media, the ratio of the sine of the angle of incidence to the sine of the angle of refraction is constant.

Question 3

Define diffraction

Answer 3

o DIFFRACTION: The spreading of waves when they pass through an opening or round an obstacle.

Question 4

Define superposition

Answer 4

o SUPERPOSITION: When two waves pass the same point at the same time, their displacements are added together to calculate the resultant displacement.

Question 5

Define interference

Answer 5

o INTERFERENCE: Superposition of coherent sources resulting in an interference pattern.

Question 6

Define constructive/destructive

Answer 6

o CONSTRUCTIVE/ DESTRUCTIVE: Interference in which the resultant is reinforced/ cancelled.

Question 7

Define coherent

Answer 7

o COHERENT: Sources of waves with a constant phase difference are coherent.