JEE Main 2020 · PhysicsNumerical answerNumerical valueHardMulti-step

JEE Main 5 September 2020, Shift 1, Physics Q21

Question 21 of 75 in this shift, Physics question 21 of 25.

A particle of mass 200 MeV/c

^2

collides with a hydrogen atom at rest. Soon after the collision the particle comes to rest, and the atom recoils and goes to its first excited state. The initial kinetic energy of the particle (in eV) is

\frac{N}{4}

. The value of N is : (Given the mass of the hydrogen atom to be 1 GeV/c

^2

) __________.

Official answer

51.00

NTA final key (Sep 2020).

Chapter: Atoms
Topic: Bohr's Atomic Model
Idea tested: Collisional Excitation

Same topic in other shifts

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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.