JEE Main 2020 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 3 September 2020, Shift 2, Physics Q10

Question 10 of 75 in this shift, Physics question 10 of 25.

Hydrogen ion and singly ionized helium atom are accelerated, from rest, through the same potential difference. The ratio of final speeds of hydrogen and helium ions is close to :

(1)5 : 7
(2)10 : 7
(3)1 : 2
(4)2 : 1Official answer

Official answer

Option 4

NTA final key (Sep 2020).

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

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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.