JEE Main 2024 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 31 January 2024, Shift 1, Physics Q57

Question 57 of 90 in this shift, Physics question 27 of 30, Section B.

An electron moves through a uniform magnetic field

\vec{B}=B_0\hat{i}+2B_0\hat{j}\ T

. At a particular instant of time, the velocity of electron is

\vec{u}=3\hat{i}+5\hat{j}\ m/s

. If the magnetic force acting on electron is

\vec{F}=5e\hat{k}\ N

, where

e

is the charge of electron, then the value of

B_0

is ________

T

Official answer

NTA final key.

Chapter: Moving Charges and Magnetism
Topic: Lorentz Force
Idea tested: Determinant Form of Magnetic Force

Same topic in other shifts

All Lorentz Force 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.