Q90 / 90 · JEE Main 2022 (24 Jun Shift 1) · Physics
A metre scale is balanced on a knife edge at its centre. When two coins, each of mass are put one on the top of the other at the mark the scale is found to be balanced at mark. The mass of the metre scale is found to be . The value of is _____ .
Correct answer: 6
Solution
Let the mass of the scale be .
The centre of mass of the scale will be at .
Applying torque balance,
Hence, the correct answer is 6.