JEE Main 2020 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 3 September 2020, Shift 1, Physics Q22

Question 22 of 75 in this shift, Physics question 22 of 25.

A person of 80 kg mass is standing on the rim of a circular platform of mass 200 kg rotating about its axis at 5 revolutions per minute (rpm). The person now starts moving towards the centre of the platform. What will be the rotational speed (in rpm) of the platform when the person reaches its centre __________.

Official answer

9.00

NTA final key (Sep 2020).

Chapter: System of Particles and Rotational Motion
Topic: Angular Momentum
Idea tested: Person Walking on a Rotating Turntable

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 108 of the 174 JEE Main shifts held from 2017 to 2026.