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A new unit (α) 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 α units if light takes 6 min 40 s to cover this distance?

Asked in JEE Main 8th April 2nd Shift 2026 · Units and conversions

Answer: (2) 400 α

Step-by-step solution

Given: t=6 min 40 s =400 s, and the new unit is α=c numerically.

Distance travelled: D=ct.

Expressed in the new unit: D/α=(ct)/c=t=400.

So D=400 α.

Why the other options are wrong

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