JEE Main 2022 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 24 June 2022, Shift 2, Physics Q39

Question 39 of 90 in this shift, Physics question 9 of 30, Section A.

A proton, a deuteron and an

\alpha

-particle with same kinetic energy enter into a uniform magnetic field at right angle to magnetic field. The ratio of the radii of their respective circular paths is :

(1) $1:\sqrt{2}:\sqrt{2}$
(2) $1:1:\sqrt{2}$
(3) $\sqrt{2}:1:1$
(4) $1:\sqrt{2}:1$ Official answer

Official answer

Option 4

NTA final key.

Chapter: Moving Charges and Magnetism
Topic: Lorentz Force
Idea tested: Trajectory Radii Ratio for Same Kinetic Energy

Same idea in other shifts

Asked 4× in all

9 Apr 2024, Shift 2 · Q44A proton and a deutron ( $q=+e$ , $m=2.0$ u) having same kinetic energies enter a region of uniform magnetic field $\vec{B}$ , moving…EasySingle correct
27 Jun 2022, Shift 2 · Q58A deuteron and a proton moving with equal kinetic energy enter into to a uniform magnetic field at right angle to the field. If $r_d$ and…EasyNumerical value
27 Aug 2021, Shift 1 · Q13Two ions of masses 4 amu and 16 amu have charges $+2$ e and $+3$ e respectively. These ions pass through the region of constant…MediumSingle correct

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.