Weight =m(R2GM)
∴49=Re2GMe×GMpRp2
Given that, Mp=9Me
∴49=(9Me)Me×Re2Rp2
Rp2=Re2×41
Rp=2Re
As, Re=R
⇒Rp=2R
JEE Main 2019 — Physics Mechanics
The ratio of the weights of a body on Earth’s surface to that on the surface of a planet is 9:4 The mass of the planet is 91th of that of the Earth. If R is the radius of the Earth, what is the radius of the planet? (Take the planets to have the same mass density)
Held on 12 Apr 2019 · Verified 6 Jul 2026.
4R
2R
3R
9R
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