Kinematics

JEE Main level, single correct, medium

73 of 308

Question 73 of 308

Two points AA and BB move from rest along a straight line with constant acceleration ff and ff ' respectively. If AA takes mm sec. more than BB and describes ' nn ' units more than BB in acquiring the same speed then

Show answer and solution

Answer: (D) (f′−f)n=12ff′m2\left(f^{\prime}-f\right) n=\frac{1}{2} f f^{\prime} m^2

v2=2f(d+n)=2f′dv=f′(t)=(m+t)f\begin{aligned} & v^2=2 f(d+n)=2 f^{\prime} d \\ & v=f^{\prime}(t)=(m+t) f \end{aligned}
eliminate dd and mm we get
(f′−f)n=12ff′m2. \left(f^{\prime}-f\right) n=\frac{1}{2} f f^{\prime} m^2 \text {. }

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: Projectile motion simulationDrag the sliders and watch the numbers in this question change.Revise Kinematics & Projectile Motion firstFormula sheet, solved examples and the traps students fall into.

More Physics practice

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