JEE Mains · Physics · STD 11 - 1. units,dimensions and measurement
A new unit \((\alpha)\) 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 \(\alpha\) units if light takes \(6\) min. \(40\) s to cover this distance?
- A \(200\,\alpha\)
- B \(400\,\alpha\)
- C \(300\,\alpha\)
- D \(500\,\alpha\)
Answer & Solution
Correct Answer
(B) \(400\,\alpha\)
Step-by-step Solution
Detailed explanation
Given that the new unit of length \(\alpha\) is chosen such that the speed of light in vacuum is \(1\,\alpha/\text{s}\). Time taken by light to cover the distance, \(t = 6\text{ min } 40\text{ s}\) \(t = 6 \times 60\text{ s} + 40\text{ s} = 400\text{ s}\) Distance between Venus…
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