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JEE Main20268 April 2026Evening ShiftPhysicsUnits and DimensionsActual

A new unit ( ) of length is chosen such that it is equal to the speed of light in vacuum. What is the distance between Venus and Earth in terms of units if light takes 6 min. 40 s to cover this distance?

Options

  1. A200 ,
  2. B400 ,
  3. C300 ,
  4. D500 ,

Correct answer

B. 400 ,

Step-by-step solution

Given that the new unit of length is chosen such that the speed of light in vacuum is 1 , / s . Time taken by light to cover the distance, t = 6 min 40 s t = 6 60 s + 40 s = 400 s Distance between Venus and Earth is given by d = c t d = 1 , / s 400 s = 400 , Answer: 400 ,

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