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Frequency of the em signal emitted by a rocket is 4 × 10 7 H z . If apparent frequency observed on earth is 3.2 × 10 7 H z , then velocity with which rocket is moving away is [speed of light = c ]

Options

  1. A0 . 5   c
  2. B0 .7 c
  3. C0 .9 c
  4. D0 . 2 c

Correct answer

D. 0 . 2 c

Step-by-step solution

We know that υ = υ 0 c - v c + v or v = ∆ υ υ 0 × c v = 0.8 × 10 7 4 × 10 7 × 3 × 10 8 = 6 × 10 7   m   s - 1 = 0.2   c

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