Two blocks of masses 2 kg and 1 kg respectively, are tied to the ends… | JEE Main 2026 (2 Apr, Shift 2)

Q3JEE Main 2026 · 2 APR · SHIFT 2Medium

Motion of Centre of Mass

Two blocks of masses 2 kg and 1 kg respectively, are tied to the ends of a string which passes over a light frictionless pulley as shown in the figure below. The masses are held at rest at the same horizontal level and then released. The distance traversed by the centre of mass in 2 s is _______ m. (Take $g = 10\text{ m/s}^2$ )

Show answer and solution

Answer: (c)

Block acceleration: $a = \frac{(2-1)g}{2+1} = \frac{10}{3}$ m/s $^2$ (2 kg down, 1 kg up).
$a_{cm} = \frac{2(a) - 1(a)}{3} = \frac{a}{3} = \frac{10}{9}$ m/s $^2$ downward.
Starting from rest: $s = \frac{1}{2}a_{cm}t^2 = \frac{1}{2}\cdot\frac{10}{9}\cdot 4 = \frac{20}{9}$
So the distance is $2.22$ m, answer (c).

Report a mistake

More questions on Motion of Centre of Mass

In projectile motion two particles of masses m₁ and m₂ have velocities V₁, and V₂…MHT CET 2024 (3 May, Shift 2)
Two particles A and B initially at rest, move towards each other under mutual force of…NEET 2023
Given below are two statements: One is labelled as Assertion (A) and the other is…NEET 2022 (Phase 2)
Four particles A, B, C and D with masses mA = m, mB = 2m, mC = 3m and mD = 4m are at the…JEE Main 2019 (8 Apr, Shift 1)
Two spherical bodies of mass M and 5M and radii R and 2R are released in free space with…NEET 2015 (AIPMT, Cancelled Paper)
A boy of mass 20 kg is standing on a 80 kg free to move long cart. There is negligible…JEE Main 2013 (23 Apr, Shift 1)
A projectile of mass M is fired so that the horizontal range is 4 km. At the highest…JEE Main 2013 (23 Apr, Shift 1)
Two persons of masses 55 kg and 65 kg respectively, are at the opposite ends of a boat…NEET 2012 (AIPMT, Prelims)

Motion of Centre of Mass question from JEE Main 2026 (2 Apr, Shift 2)

More questions on Motion of Centre of Mass