[填空题]
A laser beam is directed at tc3t;gz t,7vkm plb):q nc5.qz he Moon, 380,000 km from Earth. The becvjl5 k(1gvtkf78c ; dam diverges at 8vc 1v7 t;(5kl dfkgjcan 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
