JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 16 March 2021, Shift 2, Physics Q6

Question 6 of 90 in this shift, Physics question 6 of 30, Section A.

Amplitude of a mass-spring system, which is executing simple harmonic motion decreases with time. If mass = 500 g, Decay constant = 20 g/s then how much time is required for the amplitude of the system to drop to half of its initial value ? (

\ln 2=0.693

)

(1)34.65 sOfficial answer
(2)15.01 s
(3)0.034 s
(4)17.32 s

Official answer

Option 1

NTA final key.

Chapter: Oscillations
Topic: SHM Equations
Idea tested: Damped Amplitude Decay

Same topic in other shifts

All SHM Equations questions

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2 Apr 2025, Shift 1 · Q33A particle is subjected to two simple harmonic motions as : $x_1=\sqrt{7}\sin5t$ cm and $x_2=2\sqrt{7}\sin\left(5t+\frac{\pi}{3}\right)$ …MediumSingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 42 of the 174 JEE Main shifts held from 2017 to 2026.