JEE Mains · Physics · STD 12 - 10. Wave optics
An observer is moving with half the speed of light towards a stationary microwave source emitting waves at frequency \(10\ GHz\). What is the frequency of the microwave measured by the observer?.......\(GHz\) ( speed of light \(= 3 \times 10^8 \) \(ms^{-1}\))
- A \(10.1 \)
- B \(12.1 \)
- C \(17.3\)
- D \(15.3\)
Answer & Solution
Correct Answer
(C) \(17.3\)
Step-by-step Solution
Detailed explanation
Use relativistic doppler's effect as velocity of observer is not small as compared to light \(f=f_{0} \sqrt{\frac{c+v}{c+v}}\) ; \(V=\) relative speed of approach \(f_{0}=10\, \mathrm{GHz}\)…
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