JEE Main 2021 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 3 August 2021, Shift 1, Physics Q26

Question 26 of 90 in this shift, Physics question 26 of 30, Section B.

Two particles having position vectors

\vec{r_1} = \left(2\vec{i} + 3\vec{j}\right) m

and

\vec{r_2} = \left(-10\vec{i} + 3\vec{j}\right) m

are moving with velocities

\vec{v_1} = \left(\vec{i} - 2\vec{j}\right) m/s

and

\vec{v_2} = \left(5\vec{i} - b\vec{j}\right) m/s

. If they meet after 3 second, the value of ‘

b

' is _________.

Official answer

NTA final key.

Chapter: Motion in a Plane
Topic: Relative Velocity
Idea tested: 2D Collision Condition

Same topic in other shifts

All Relative Velocity questions

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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.