[填空题]
A laser beam is directed at the Moon, 380,000 km fjz)/dtn a*c1z zl* i(zrom Earth. Thqdb9*/s;: cli hw/ nlj,r y9gue beam diverges at an anglehqrc/9 *u9sl g:w, / jnlib;dy $\theta$ (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
