[填空题]
A laser beam is directed+eo-82tavj-hk),vgq -b klvx xq5ip) at the Moon, 380,000 km from Earth. The beam divergk :p kxu8ryjf)qzn6/5es at an anpkn/q6zx5: )f kr8yj ugle $\theta$ (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
