Oscillations

JEE Main level, numerical answer, medium

84 of 194

Question 84 of 194

The general displacement of a simple harmonic oscillator is x=Asin⁡ωtx=A\sin \omega t. Let TT be its time period. The slope of its potential energy (UU) – time (tt) curve will be maximum when t=Tβt=\dfrac{T}{\beta }. The value of β\beta is ______.

Show answer and solution

Answer: 8

Given here, displacement x=Asin⁡(ωt)x=A\sin \left(\omega t\right)
Now, potential energy of a simple harmonic oscillator is
U=12mω2x2=12mω2A2sin⁡2(ωt)U=\dfrac{1}{2}m{\omega }^{2}{x}^{2}=\dfrac{1}{2}m{\omega }^{2}{A}^{2}{\sin }^{2}\left(\omega t\right),
So, slope of potential energy and time curve is
dUdt=12mω3A22sin⁡2ωt\dfrac{dU}{dt}=\dfrac{1}{2}\dfrac{m{\omega }^{3}{A}^{2}}{2}\sin 2\omega t
Now,
(dUdt)max{\left(\dfrac{dU}{dt}\right)}_{max} will be maximum when sin⁡2ωt=1\sin 2\omega t=1
⇒2ωt=π2⇒2(2πT)t=π2⇒t=T8⇒β=8\Rightarrow 2\omega t=\dfrac{\pi }{2} \Rightarrow 2\left(\dfrac{2\pi }{T}\right)t=\dfrac{\pi }{2} \Rightarrow t=\dfrac{T}{8} \Rightarrow \beta =8

JEE Main question paper PDF

Open a shift to read the full paper on this page, or download it.

JEE Main 2025 Apr 2 Shift 1 question paper

Open Download PDF

Opening paper…

Explain it as a whiteboard videoStep-by-step, in Hinglish or English. Your first video needs no login.Solved it on paper but got it wrong?Upload a photo of your working. Mistake Doctor marks the exact line that broke.
See it move: Simple pendulum simulationDrag the sliders and watch the numbers in this question change.

More Physics practice

JEE Main Physics practice question on Oscillations (Energy of Simple Harmonic Motion), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.