[填空题]
A laser beam is dire h9jl), sztvw+9lp s*octdm3x iz kmsk( -a9sj7w-8 z(veed at the Moon, 380,000 km from Earth. The beam diverges at an 9jk em-87ma-d(vzszixs(3wk 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
