Physics · Rotational Dynamics

JEE Main 2026 — 6 April, Evening Shift — Question 2

A solid sphere (A) of mass 5m and spherical shell (B) of mass m, both having same radius, are placed on a rough surface. When a force of same magnitude is applied tangentially at the highest points of A and B, they start rolling without slipping with an acceleration of $a_A$ and $a_B$ respectively. The ratio of $a_A$ and $a_B$ is

Option A:
5:21
Correct
Option B:
6:10
Option C:
21:25
Option D:
1:5

Answer: A

Step-by-step solution

For solid sphere: $I = \frac{2}{5}MR^2$ . For spherical shell: $I = \frac{2}{3}mR^2$ . Using torque and force equations, solving gives $a_A = \frac{2F}{7m}$ and $a_B = \frac{6F}{5m}$ , ratio = $\frac{2/7}{6/5} = \frac{10}{42} = \frac{5}{21}$ .

Answer key and solution verified before publishing.

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Exam: JEE Main 2026
Paper: 6 April, Evening Shift
Subject: Physics
Chapter: Rotational Dynamics
Topic: Rolling Motion