Interference

Question 1

What is a coherent wave source?

Answer 1

Coherent waves are coherent if they have a constant phase relationship
(They also have the same frequency)

Question 2

If two waves are in phase what are they?

Answer 2

Vibrating in exactly the same way, at the same time

Question 3

What is constructive interference?

Answer 3

When two waves are in phase, crest to crest or trough to trough

Question 4

What is destructive interference?

Answer 4

When two waves are exactly out of phase and cancel each other out, crest to trough

Question 5

What is interference the test for?

Answer 5

A wave

Question 6

What is path difference?

Answer 6

Path difference is the number of wavelengths as a maximum or minimum

Question 7

Describe the wavelengths at maximums and minimums in terms of path difference

Answer 7

Path difference at a Maximum is a whole number of wavelengths
Path difference at a minimum is a half number of wavelengths

Question 8

What is a grating and what’s the grating equation?

Answer 8

Consists of many equally spaced slits to pass light through.

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