[填空题]
A laser beam is direc xr ai16qogzek *-r;m)n )soy2ted at thevvi+ xwzf62: y6yc kfb(m/yx* Moon, 380,000 km from Earth. The beam diverges at :vy*2+vx/f(c x6wiy kbfmy6zan 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
