[填空题]
A laser beam is direct rlm/x3djgktej i8(+4m 8( xrzed at the Moon, 380,000 km from Earthiqo ,-zwiqk e. eso)x ;r*.ni4. The beam diverges at an angle )o.e4ier;o .ixqk*zs, ni -wq$\theta$ (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
