JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 16 March 2021, Shift 2, Physics Q12

Question 12 of 90 in this shift, Physics question 12 of 30, Section A.

The half-life of

\mathrm{Au^{198}}

is 2.7 days. The activity of 1.50 mg of

\mathrm{Au^{198}}

if its atomic weight is 198 g

\mathrm{mol^{-1}}

is, (

N_A=6\times10^{23}

/mol).

(1)240 Ci
(2)357 CiOfficial answer
(3)252 Ci
(4)535 Ci

Official answer

Option 2

NTA final key.

Chapter: Nuclei
Topic: Radioactive Decay
Idea tested: Activity and Rate of Decay

Same topic in other shifts

All Radioactive Decay questions

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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.