228s13-l04

# The distance to a or b is an even number of

This preview shows page 1. Sign up to view the full content.

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

Unformatted text preview: ’ - ``peaks’’ and ``valleys’’ are emitted at the same time from each source. The waves are also ``in phase’’ at points a and b, but not at point c. The distance to a or b is an even number of wavelengths different. The distance to point c is not. Sunday, February 24, 2013 Maxima and Minima At some places the waves add up and you get constructive interference and maxima - for || E ﬁelds, the sum is (E1+E2)cos(ωt). At other places the waves add up ``out of phase’’ and you get destructive interference and minima - if the E ﬁelds are ||, the sum is always 0! And at most places you are somewhere in between these limits. Sunday, February 24, 2013 Let's see a demo and a simulation of 2source wave interference. iClicker I am going to move the sources apart. Will the minima / maxima lines move? a) No! Of course not. b) Yes! The angles between them increase and you get fewer of them. c) Yes! The angles between them decrease and you get more of them. d) Yes! You get more minima lines but fewer maxima lines. e) Yes! You get more maxima lines but fewer minima lines. Sunday, February 24, 2013 iClicker: I am going to shift the wave frequency from red to blue. (Make the wave length shorter.) What happens to the angles of the minima lines? a) They stay the same. Nothing changes. b) The angles decrease - the lines move in and there are more of them. c) The angles increase -...
View Full Document

## This document was uploaded on 02/18/2014 for the course PHYS 228 at Rutgers.

Ask a homework question - tutors are online