Topic 5 - Waves and Particle Nature of Light

Question 1

Define oscillation

Answer 1

Motion that repeats at regular intervals (periodic oscillation/harmonic motion)

Question 2

One wave cycle = ?

Answer 2

One oscillation (2π/360°)

Question 3

Define wave phases

Answer 3

They describe the stage of a wave’s oscillation

Question 4

What is the phase difference when waves are in antiphase?

Answer 4

π (180°)

Question 5

What is the phase difference when waves are said to be ‘in phase’?

Answer 5

They are at the same stage, so 0

Question 6

What is the phase difference when waves are said to be in quadrature?

Answer 6

π/2 (90°)

Question 7

f = ?

Answer 7

1/T

Question 8

Transverse waves have oscillations ___ to its propagation?

Answer 8

Perpendicular

Question 9

Longitudinal waves have oscillations ___ to its propagation?

Answer 9

Parallel

Question 10

What does the microphone in the oscilloscope traces core practical do?

Answer 10

Uses small movements of its diaphragm to produce an electrical signal that mimics variation of pressure/displacement in a wave

Question 11

What happens to amplitude when two waves (with same amplitude) are in phase?

Answer 11

Amplitude doubles

Question 12

What happens to amplitude when two waves (with same amplitude) are in antiphase?

Answer 12

No amplitude (think noise cancelling)