Conserving momentum
2m2v+mv=(m+2m)vf
vf=4×23m2mV=65V
vf<vorb(=v) thus the combined mass will go on to an elliptical path
JEE Main 2020 — Physics Mechanics
A body A of mass m is moving in a circular orbit of radius R about a planet. Another body B of mass 2m collides with A with a velocity which is half (2v) the instantaneous velocity v of A. The collision is completely inelastic. Then, the combined body:
Held on 9 Jan 2020 · Verified 6 Jul 2026.
continues to move in a circular orbit
Escapes from the Planet's Gravitational field
Falls vertically downwards towards the planet
starts moving in an elliptical orbit around the planet
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