All Problems

Optics of Moving Sources

Problem 5.229

A plane electromagnetic wave of frequency \(\omega_{0}\) falls normàlly on the surface of a mirror approaching with a relativistic velocity \(V\). Making use of the Doppler formula, find the frequency of the reflected wave. Simplify the obtained expression for the case \(V \ll c\).

Reveal Answer
5.229.ω=ω0(1+β)/(1β), where β=V/c;ωω0(1+2V/c)\begin{array}{l} 5.229 . \omega=\omega_{0}(1+\beta) /(1-\beta), \quad \text { where } \quad \beta=V / c ; \quad \omega \approx \\ \approx \omega_{0}(1+2 V / c) \end{array}