For the one-dimensional motion described by $x(t) = t - \sin t$ A. $v(t) 0$ B. $x(t) > 0$ for all $t > 0$ C. $v(t)$ lies in between 0 and 2 D. $a(t) > 0$ for all t > 0 E. $a(t)$ lies in between 2 and 3 Choose the correct answer from the options given below :

JEE Main 2021 · PhysicsMultiple choiceOtherMediumMulti-step

JEE Main 3 August 2021, Shift 1, Physics Q2

Question 2 of 90 in this shift, Physics question 2 of 30, Section A.

For the one-dimensional motion described by

x(t) = t - \sin t

v(t) < 0

for all

t > 0

x(t) > 0

for all

t > 0

v(t)

lies in between 0 and 2 D.

a(t) > 0

for all t > 0 E.

a(t)

lies in between 2 and 3 Choose the correct answer from the options given below :

(1)A, D, E only
(2)B, C onlyOfficial answer
(3)B, C, E only
(4)C, E only

Official answer

Option 2

NTA final key.

Chapter: Motion in a Straight Line
Topic: Kinematics in 1D
Idea tested: Calculus in Kinematics

Same idea in other shifts

Asked 9× 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.