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..