Chapter 12 - Waves Flashcards
2nd order maxima- path difference
2 λ
2nd order minima- path difference
1.5 λ
1st order maxima- path difference
λ
1st order minima- path difference
λ/2
central maxima
0
2nd order maxima- phase difference
4π
2nd order minima- phase difference
3π
1st order maxima- phase difference
2π
1st order minima- phase difference
π
define path difference
The difference in distance travelled by each wave
what does superpose mean
when 2 waves overlap
What is the difference between interference and superposition
Superposition is the actual physical phenomena, but the interference is what we actually see. Interference is the pattern or effect that is observes by the superposition of waves.
What happens if 2 waves are in phase when they meet?
This will double their maximum, causing a constructive interference.
What happens if 2 waves are in antiphase when they meet?
They will completely cancel each other out, leaving a destructive interference.
What happens if 2 waves are out of phase when they meet?
There will be a degree of destructive interference, but not total.
How is intensity and amplitude related
Intensity = k * amplitude2 (squared)
What is coherent waves
When 2 waves have the same frequency and they maintain the same phase difference.
What is minima
Destructive interference
What is maxima
Constructive interference
How can you find the phase difference from the path difference
For 2 coherent wave differences, PLD as a fraction of the wavelength gives you the phase difference.