Chapter 37, Problem 84P

To determine

To find:

a) The period $\tau$ of the timer as detected by observer $A$

b) Show that at the receiver $R,$ the time interval between pulses arriving from $T$ is not $\tau$ or ${\tau }_0$ but

${\tau }_R={\tau }_0\sqrt{\frac{c+v}{c-v}}$

c) Explain why receiver $R$ and observer $A$, who are in the same reference frame, measure a different period for the transmitter.