Learn

Friday, 9 October

JEE Main 2025 · PhysicsNumerical answerNumerical valueHardMulti-step

JEE Main 8 April 2025, Shift 2, Physics Q46

Question 46 of 75 in this shift, Physics question 21 of 25, Section B.

A 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 with masses was placed on a wedge keeping the distance between wedge point and 200 gm weight as 25 cm. Initially the masses were not at balance. A beaker is placed beneath the unknown mass and water is added slowly to it. At given point the masses were in balance and half volume of the unknown mass was inside the water. (Take the density of unknown mass is more than that of the water, the mass did not absorb water and water density is 1 gm/cm3^3.) The unknown mass is _____ kg.

Official answer

3

NTA final key.

Chapter
System of Particles and Rotational Motion
Topic
Torque and Equilibrium
Idea tested
Torque due to Buoyancy

Same topic in other shifts

All Torque and Equilibrium questions
  1. 2 Apr 2025, Shift 1 · Q28A 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…MediumSingle correctHas a figure
  2. 2 Apr 2025, Shift 1 · Q30A square Lamina OABC of length 10 cm is pivoted at 'O'. Forces act at Lamina as shown in figure. If Lamina remains stationary, then the…MediumSingle correctHas a figure
  3. 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
  4. 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
  5. 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
  6. 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

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.