Mearth=64Mmoon and Rearth=4Rmoon
Given: E=RearthGMearthm
Now, for the moon,
E′=RmGMmm
=4RearthG64Mearthm=16RearthGMearthm=16E
JEE Main 2019 — Physics Mechanics
A rocket has to be launched from earth in such a way that it never returns. If E is the minimum energy delivered by the rocket launcher, what should be the minimum energy that the launcher should have, if the same rocket is to be launched from the surface of the moon? Assume that the density of the earth and the moon are equal and that the earth's volume is 64 times the volume of the moon.
Held on 8 Apr 2019 · Verified 6 Jul 2026.
64E
4E
32E
16E
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