Interference and superposition

What does the principle of superposition say?

We call it _______ interference when two waves add together their amplitudes to make a larger amplitude

What is total destructive interference?

What is the phase difference between two points on a wave?

Which of these are units of phase difference

• seconds

• rad s^-1

• radians

• degrees

• metres

What is the phase difference when two points on a wave are exactly out of phase?

• π

• 360 degrees

• π/2

• 2π

• 90 degrees

How many nodes does a fundamental mode of vibration have?

• 0

• 1

• 2

• 3

• 4

Which of these cannot be polarised?

• waves on a vibrating string

• ultrasound

• x-rays

• 5G signals

Describe fluorescence (keywords: incident, excite, de-excite, photon)