Answer
$50m$
Work Step by Step
We can use the given wavelength, lambda, the diameter of the telescope, d, and the distance from the earth to the moon, L, in equation (36-17) to find the separation of the two points on the moon, D.
$L=\frac{Dd}{1.22 \lambda}$ (36-17)
Solving for D, we obtain:
$D=\frac{L*1.22\lambda}{ d}$
$D=\frac{1.22*3.82*10^{8}m*550*10^{-9}m}{5.1m}$
$D\approx 50m$
