JEE Main 2025 — Rotational Motion Question with Solution
JEE Main 2025 (29 Jan Shift 2)
Question
Three equal masses are kept at vertices (A, B, C) of an equilateral triangle of side a in free space. At , they are given an initial velocity and . Here, and are unit vectors along the edges of the triangle. If the three masses interact gravitationally, then the magnitude of the net angular momentum of the system at the point of collision is :
Choose an option
Show full solutionCorrect option: C
Correct answer
C a
Step-by-step explanation
Angular momentum of one mass about point $\begin{aligned} L & =m v d \\ & =m v_0 \cdot \frac{a}{2 \sqrt{3}} \end{aligned}$ Net angular momentum about point $\begin{aligned} L_{\text {net }} & =32 \\ & =\frac{\sqrt{3} m v_0 a}{2} \end{aligned}$
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This is a previous-year question from JEE Main 2025, covering the Rotational Motion chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.