Learn

Friday, 9 October

JEE Main 2025 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 2 April 2025, Shift 1, Physics Q28

Question 28 of 75 in this shift, Physics question 3 of 25, Section A.

A cord of negligible mass is wound around the rim of a wheel supported by spokes with negligible mass. The mass of wheel is 10 kg and radius is 10 cm and it can freely rotate without any friction. Initially the wheel is at rest. If a steady pull of 20 N is applied on the cord, the angular velocity of the wheel, after the cord is unwound by 1 m, would be :

The figure, in words

Wheel (circle) with radius R marked from centre to rim; a cord wound on the rim hangs vertically down from the right side of the rim with a downward force F = 20 N applied at its end.
  1. (1)10 rad/s
  2. (2)20 rad/sOfficial answer
  3. (3)30 rad/s
  4. (4)0 rad/s

Official answer

Option 2

NTA final key.

Chapter
System of Particles and Rotational Motion
Topic
Torque and Equilibrium
Idea tested
Work Done by Constant Torque

Same topic in other shifts

All Torque and Equilibrium questions
  1. 2 Apr 2025, Shift 2 · Q46A wheel of radius 0.2 m rotates freely about its center when a string that is wrapped over its rim is pulled by force of 10 N as shown in…EasyNumerical valueHas a figure
  2. 8 Apr 2025, Shift 2 · Q46A cube having a side of 10 cm with unknown mass and 200 gm mass were hung at two ends of an uniform rigid rod of 27 cm long. The rod along…HardNumerical value
  3. 9 Apr 2024, Shift 1 · Q33A heavy iron bar, of weight W is having its one end on the ground and the other on the shoulder of a person. The bar makes an angle…EasySingle correct
  4. 9 Apr 2024, Shift 1 · Q52A string is wrapped around the rim of a wheel of moment of inertia 0.40 kgm20.40\ \mathrm{kgm^2} and radius 1010 cm. The wheel is free to rotate…EasyNumerical value
  5. 13 Apr 2023, Shift 2 · Q52A light rope is wound around a hollow cylinder of mass 5 kg and radius 70 cm. The rope is pulled with a force of 52.5 N. The angular…MediumNumerical value
  6. 24 Jun 2022, Shift 1 · Q60A metre scale is balanced on a knife edge at its centre. When two coins, each of mass 10 g are put one on the top of the other at the 10.0…MediumNumerical value

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. This question needs a figure we do not reproduce; it is described in words above. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.