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Three Observers A, B and C Measure the Speed of Light Coming from a Source to Be νA, νBand νC. a Moves Towards the Source and C Moves Away from the Source at the Same Speed. - Physics

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Question

Three observers A, B and C measure the speed of light coming from a source to be νA, νBand νC. A moves towards the source and C moves away from the source at the same speed. B remains stationary. The surrounding space is vacuum everywhere.

(a) \[\nu_A  >  \nu_B  >  \nu_C\]

(b) \[\nu_A  <  \nu_B  <  \nu_C\]

(c) \[\nu_A  =  \nu_B  =  \nu_C\]

(d) \[\nu_B  = \frac{1}{2}\left( \nu_A + \nu_C \right)\]

Short/Brief Note
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Solution

(c) \[\nu_A  =  \nu_B  =  \nu_C\]

(d) \[\nu_B  = \frac{1}{2}\left( \nu_A + \nu_C \right)\]

 

Since the speed of light is a universal constant, \[\nu_A = \nu_B = \nu_C = 3 \times  {10}^8\]

\[\nu_B  = \frac{1}{2}\left( v_A + v_C \right)\]

This expression also implies that vA = vB = vC.

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Chapter 17: Light Waves - MCQ [Page 380]

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HC Verma Concepts of Physics Vol. 1 [English] Class 11 and 12
Chapter 17 Light Waves
MCQ | Q 5 | Page 380

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