(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Two coherent sources of radio waves, A and B, are 5.00 m apart. Each source emits waves

with wavelength 6.00 m. Consider points only along the line connecting the two sources.

(a) At what distance from source A is there constructive interference between points A and

B?

(b) At what (two) distances from source A is there destructive interference between points

A and B?

Suppose the two sources differ in phase by 90 instead.

(c) At what point(s) between the two sources do we get constructive interference?

(d) What is the nearest point to source A, but on the other side from source B, where we

get destructive interference?

2. Relevant equations

constructive: m*2pi= 2pi delta x / wavelength + phase constant

destructive: (m+1/2) *2pi= 2pi delta x / wavelength + phase constant

3. The attempt at a solution

for parts a/b, i am using phase constant = 0.

i used 0,1,... for m, and plugged into the equation to solve for delta x.

2pi= 2pi delta x / 6m + 0

delta x= 0m, 6m then is 0m the only distance from a where there is constructive interference?

how do you take into account that the sources are 5m apart?

for parts c/d, i am using phase constant = 90

2pi= 2pi delta x / 6m + pi/2

delta x= 9/2 m, 21/2 m is 4.5 m the distance from a for constructive interference?

i am assuming there's something i'm missing since the hints from the problem suggest 1 answer to part a, 2 distances for part b, etc.

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# Homework Help: Radio waves: constructive and destructive interference 1-dimension

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