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A particle of mass m is moving in time t on a trajectory given by, =10α t^2 i+5β (t-5) j where α and β are dimensional constants. The angular…

JEE Main 2021 — Physics Mechanics

2021integerhard

A particle of mass mmm is moving in time ttt on a trajectory given by,

r⃗=10αt2i^+5β(t−5)j^\vec{r}=10\alpha {t}^{2}\hat{i}+5\beta (t-5)\hat{j}r=10αt2i^+5β(t−5)j^​

where α\alphaα and β\betaβ are dimensional constants.

The angular momentum of the particle becomes the same as it was for t=0t=0t=0 at time t=t=t=_____ seconds.

Official previous-year question

Held on 25 Jul 2021 · Verified 6 Jul 2026.

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