Question

Va rog sa ma ajutați...

Answer 1

3.

Legea refractiei: n*sin i=n' sin r <=>1*sin 45°=n'*sin 30°=>n'=sin 45°/sin 30°=√2/2/1/2=√2=1,41

n'=c/v=>v=c/n'=3=10⁵/1.41=2,12*10⁵ km/s=2,12*10⁸ m/s -> b

4.

β=1/2

β=x₂/x₁=>x₂=βx₁

Legea lentilelor subtiri: 1/x₂-1/x₁=1/f=>x₁=f(1-β)/β=-40(1-1/2)/1/2=-80*1/2=-40 cm

|x₁|=40 cm->c