JEE Main 2025 · PhysicsNumerical answerNumerical valueMediumMulti-step

JEE Main 4 April 2025, Shift 2, Physics Q50

Question 50 of 75 in this shift, Physics question 25 of 25, Section B.

A solid sphere with uniform density and radius R is rotating initially with constant angular velocity

(\omega_1)

about its diameter. After some time during the rotation its starts loosing mass at a uniform rate, with no change in its shape. The angular velocity of the sphere when its radius become

R/2

x\omega_1

. The value of

x

is __________.

Official answer

NTA final key.

Chapter: System of Particles and Rotational Motion
Topic: Angular Momentum
Idea tested: Angular Momentum of a Shrinking Sphere

Same topic in other shifts

All Angular Momentum questions

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.