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

A radiotelescope is positioned at a height of h=150m on a cliff overlooking the sea. A very distant galaxy emitting radiowaves, wavelength 3m, is at an angle [tex]\theta[/tex] above the horizion. The radiowaves reach the telescope both directly and after reflection off the water surface. Show that if [tex]\theta[/tex]=57degrees, then the 2 rays interfere destructively, so that the signal received is zero. Note that the refractive index,n,of the sea is greater than that of air

2. Relevant equations

dsin[tex]\theta[/tex]=(m+1/2)[tex]\lambda[/tex] for destructive interference.

3. The attempt at a solution

Tried substituting the values into the equation, with d=2hsin[tex]\theta[/tex], and expected to get m as an integer, but didnt..

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# Radiowave interference

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