A planet has the same mass as the Earth but half its radius. If at the Earth's surface is , what is the gravitational field strength at the planet's surface?
Answer and explanation
Correct answer: C.
- Step 1: Surface gravity , so for the same mass.
- Step 2: Halving multiplies by , so N/kg.
Answer
.
Why not the others: : scales with the radius ratio only, not its square. : divides instead of multiplying. : divides by the square of the ratio.
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