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The magnifying power of a telescope with tube length 60 c m is 5 . What is the focal length of its eye piece?

Options

  1. A20 c m
  2. B40 c m
  3. C30 c m
  4. D10 c m

Correct answer

D. 10 c m

Step-by-step solution

m = f 0 f e 5 = f 0 f e f o = 5 f e f o + f e = 60 6 f e = 60 f e = 10

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