Chapt21_22_VG2

# Chapt21_22_VG2 - Incoherent vs Out of Phase Incoherent Two...

This preview shows pages 1–6. Sign up to view the full content.

Incoherent vs Out of Phase Coherent, but out of phase . Two signals have the same frequency, but one leads or lags the other. -1.5 -1 -0.5 0 0.5 1 1.5 -5 0 5 10 15 20 25 30 35 Field t -1.5 -1 -0.5 0 0.5 1 1.5 -5 0 5 10 15 20 25 30 35 t Incoherent Two signals have different frequencies. Sometimes the same sign, sometimes opposite signs.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Fields in slits are coherent but out of phase Diffraction pattern shifts
E ( r , t ) = A ( r 1 )cos( kr 1 ω t + φ 1 ) + A ( r 2 )cos( kr 2 ω t + φ 2 ) Field and Intensity far from sources suppose A ( r 1 ) = A ( r 2 ) E ( r , t ) 2 A cos( k Δ r 2 + φ 1 φ 2 2 )cos( k r ω t + φ 1 + φ 2 2 ) Trigonometry cos( A ) + cos( B ) = 2cos( A + B 2 )cos( A B 2 ) Δ r = r 1 r 2 r = r 1 + r 2 2 Field amplitude depends on space Field oscillates in time. Constructive interference when k Δ r 2 + φ 1 φ 2 2 = m π d sin θ = λ m φ 1 φ 2 2 π

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
A.They fade out and disappear. B. They get out of focus. C. They get brighter and closer together. D.They get brighter and farther apart. E. They get brighter but otherwise do not change. Suppose the viewing screen in the figure is moved closer to the double slit. What happens to the interference fringes?
Huygen’s Principle

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 12/27/2011 for the course PHYSICS 270 taught by Professor Drake during the Fall '08 term at Maryland.

### Page1 / 38

Chapt21_22_VG2 - Incoherent vs Out of Phase Incoherent Two...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online