[填空题]
A laser beam is directed at the Moon, 380,000 km 0ja*fi+t-tp j fro4.t;7y5hcl/ ,u(e1utqo0x i k eletnxm Earth. The beam diverges aokc;u/u5tn .hyixq7l(e le x1e4,0ttt an 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
