Kinematics

JEE Main level, single correct, medium

121 of 308

Question 121 of 308

A body of mass 2 kg moving with velocity of v→in=3i^+4j^ms−1\overrightarrow{\mathrm{v}}_{\mathrm{in}}=3 \hat{\mathrm{i}}+4 \hat{\mathrm{j}} \mathrm{ms}^{-1} enters into a constant force field of 6 N directed along positive z -axis. If the body remains in the field for a period of 53\frac{5}{3} seconds, then velocity of the body when it emerges from force field is

Show answer and solution

Answer: (B) 3i^+4j^+5k^3 \hat{\mathrm{i}}+4 \hat{\mathrm{j}}+5 \hat{\mathrm{k}}

a→=B2k^=3k^,t=53 su→=3i^+4j^v→=u→+a→t=3i^+4j^+5k^\begin{aligned} & \overrightarrow{\mathrm{a}}=\frac{\mathrm{B}}{2} \hat{\mathrm{k}}=3 \hat{\mathrm{k}}, \mathrm{t}=\frac{5}{3} \mathrm{~s} \\ & \overrightarrow{\mathrm{u}}=3 \hat{\mathrm{i}}+4 \hat{\mathrm{j}} \\ & \overrightarrow{\mathrm{v}}=\overrightarrow{\mathrm{u}}+\overrightarrow{\mathrm{a}} \mathrm{t}=3 \hat{\mathrm{i}}+4 \hat{\mathrm{j}}+5 \hat{\mathrm{k}}\end{aligned}

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 (Non-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.