JEE Main 2021 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 3 August 2021, Shift 2, Physics Q25

Question 25 of 90 in this shift, Physics question 25 of 30, Section B.

A sample undergoing beta decay, reduced to

\frac{1}{16}^{\mathrm{th}}

of its initial mass in 48 years. Its half life period is

\underline{\hspace{2em}}

years.

Official answer

NTA final key.

Chapter: Nuclei
Topic: Radioactive Decay
Idea tested: Half-Life Calculations

Same idea in other shifts

Asked 5× in all

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.