JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 4 August 2021, Shift 2, Physics Q18

Question 18 of 90 in this shift, Physics question 18 of 30, Section A.

The position time relation of a body of mass 0.02 kg is given by (one-dimensional motion) x = 9 cm (for t = 3, 9, 15, 21s ..........) x = 0 cm (for t = 0 , 6, 12, 18, 24s ..........) If the time between two consecutive impulse is ‘3s’, find the magnitude of each impulse.

(1) $1.2 \times 10^{-3}$ kg m/sOfficial answer
(2)1.2 kg m/s
(3) $1.2 \times 10^{-1}$ kg m/s
(4)1200 g cms $^{-1}$

Official answer

Option 1

NTA final key.

Chapter: Laws of Motion
Topic: Newton's Laws of Motion
Idea tested: Momentum Formulation (F = dp/dt)

Same idea in other shifts

Asked 7× in all

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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 108 of the 174 JEE Main shifts held from 2017 to 2026.