[填空题]
A laser beam is directed at the Moon,fq7*ll(jz: xz;*ses:m7i )ej 9 og vxt 380,000 km from7movy-3;0s ow *joasxf0m s;b4 de fs0 Earth. The beam diverges at anfs s-m0jvay;bos0 e7d*x;sfo043m wo angle $\theta$ (Fig. 8–37) of $1.4\times10^{-5}$ rad What diameter spot will it make on the Moon? m
Post time 2025-2-18 20:00:22
