BSc Nursing GNM 2019 Solved Paper

Since, the Doppler shift affects the wave incident upon the aeroplane as well as the wave reflected back to the radar, the change in frequency observed by a radar due to an aeroplane moving at relative velocity vA (given) is twice than that from the aeroplane emitting the wave, i.e.
∆v=2⋅‌

vA

c

v
Therefore, the velocity of aeroplane is vA=c‌

∆v

2v