JEE Main 2017 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 2 April 2017 (offline), Physics Q13

Question 13 of 90 in this shift, Physics question 13 of 30.

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 ? (speed of light

=3\times10^8\ \mathrm{ms^{-1}}

)

(1)10.1 GHz
(2)12.1 GHz
(3)17.3 GHzOfficial answer
(4)15.3 GHz

Official answer

Option 3

CBSE answer key (25/04/2017, used for result).

Chapter: Dual Nature of Radiation and Matter
Topic: Doppler Effect
Idea tested: Exact Relativistic Doppler Formula

Same topic in other shifts

All Doppler Effect questions

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Question text from the official JEE Main paper published by NTA (CBSE ran the 2017 exam); answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.