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Saturday, 31 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

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  6. 10 Apr 2023, Shift 2 · Q53A force of −Pk^-P\hat{k} acts on the origin of the coordinate system. The torque about the point (2, -3) is P(ai^+bj^)P(a\hat{i} + b\hat{j}). The…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 108 of the 174 JEE Main shifts held from 2017 to 2026.