[填空题]
A laser beam is directed at the Moon, zje69;*9jpbxdh;) /oudohyd7j5nlb 380,000 km from Earth.htlt+.,w d*u k The beam diverges au h*wkttl., +dt an 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
