JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyConceptual

JEE Main 4 August 2021, Shift 1, Physics Q9

Question 9 of 90 in this shift, Physics question 9 of 30, Section A.

Assume there is a possibility of constant Electric field and Magnetic field and a charged particle under the influence of these forces tries to move along a circle. Identify which of the following are possible.

(1)E≠0, B≠0
(2)E=0, B=0
(3)E≠0, B=0
(4)E=0, B≠0Official answer

Official answer

Option 4

NTA final key.

Chapter: Moving Charges and Magnetism
Topic: Lorentz Force
Idea tested: Circular Motion in Uniform B-Field

Same idea in other shifts

Asked 7× in all

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18 Mar 2021, Shift 2 · Q16A proton and an $\alpha$ -particle, having kinetic energies $K_p$ and $K_\alpha$ respectively, enter into a magnetic field at right angles.…MediumSingle correct
9 Jan 2020, Shift 2 · Q14An electron gun is placed inside a long solenoid of radius $R$ on its axis. The solenoid has $n$ turns/length and carries a current $I$ .…MediumSingle correctHas a figure

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.