[填空题]
A laser beam is directed at the Moon, 380,000 km frohda,zr75 ,zzt6w u9dc m Earth.+wzh s5 +khe*ig;zf 2d The beam diverges at an angzw+ izhd ;s+ k*ehf2g5le $\theta$ (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
