[填空题]
A laser beam is directed a1totd x;dz cfa( q)*9r6 0gaewt the Moos/6r )mqs:tb dze1 6jan, 380,000 km from Earth. The beam diverges at an jsd)zt6b1r 6q: m ae/sangle $\theta$ (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
