Physics · Rotational Dynamics

JEE Main 2024 — 1 February, Shift 2 — Question 59

A uniform rod AB of mass 2 kg and Length 30 cm at rest on a smooth horizontal surface. An impulse of force 0.2 Ns is applied to end B. The time taken by the rod to turn through at right angles will be πxs\frac{\pi}{\mathrm{x}} \mathrm{s}, where x=\mathrm{x}= _______\_\_\_\_\_\_\_ .

Answer: 4

Numerical answer — enter this value.

Step-by-step solution

Icm=ML212=2×(0.3)212=0.096\mathrm{I}_{\mathrm{cm}}=\frac{\mathrm{ML}^{2}}{12}=\frac{2 \times(0.3)^{2}}{12}=\frac{0.09}{6} M=Icm(ωf−ωi)\mathrm{M}=\mathrm{I}_{\mathrm{cm}}\left(\omega_{\mathrm{f}}-\omega_{\mathrm{i}}\right) 0.03=0.096(ωf)0.03=\frac{0.09}{6}\left(\omega_{\mathrm{f}}\right) ωf=2rad/s\omega_{\mathrm{f}}=2 \mathrm{rad} / \mathrm{s} θ=ωt\theta=\omega \mathrm{t} t=θω=π2×2=π4sec⁡\mathrm{t}=\frac{\theta}{\omega}=\frac{\pi}{2 \times 2}=\frac{\pi}{4} \sec. X=4\mathrm{X}=4

Solution figure

Answer key and solution verified before publishing.

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Exam
JEE Main 2024
Subject
Physics
Chapter
Rotational Dynamics
Topic
Angular Momentum and its Conservation
A uniform rod AB of mass 2 kg and Length 30 cm at rest on a smooth… | JEE Main 2024 PYQ with Solution · DhiX AI