A satellite is moved to an orbit with four times the orbital radius. By what factor does its orbital period change?
Answer and explanation
Correct answer: D. It is multiplied by
- Step 1: Kepler's third law: .
- Step 2: gives , so .
Answer
It is multiplied by .
Why not the others: It is multiplied by : treats the period as proportional to the radius. It is multiplied by : takes the square root of the radius ratio. It is multiplied by : squares the radius ratio.
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