A planet has the same mean density as Earth but is three times larger in radius. If Earth’s surface gravity is g, then gravity on the planet is:
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A planet has the same mean density as Earth but is three times larger in radius. If Earth’s surface gravity is g, then gravity on the planet is:

G1 Physics · Accepted Answer

Step 1: For a homogeneous sphere, M=(4π/3)ρR³ and g=GM/R²=(4π/3)GρR. Step 2: At equal density, surface gravity scales with radius; g′=3g. Final answer: D — 3g.