# Relativistic Doppler effect

by fluidistic
Tags: doppler, effect, relativistic
 PF Gold P: 3,207 1. The problem statement, all variables and given/known data A car is getting closer to a radar as a speed of 135 km/h. If the radar works at a $$2 \times 10 ^{9} Hz$$, what difference of frequency is observed for the radar? 2. Relevant equations $$\mu=\frac{\mu _0 \sqrt {1- \frac{v^2}{c^2}}}{1-\frac{v}{c}}$$ 3. The attempt at a solution I converted 135 km/h into m/s, which gave me $$\frac { 1350 m }{36 s}$$. Then I applied the formula and $$\mu - \mu _0$$ gave me $$1.024 \times 10^{13} Hz$$ which seems WAY too big to be realistic. Am I missing something? Is it a wrong formula?!