JEE Main 2023PhysicsNuclear PhysicsEasyMCQ

JEE Main 2023 — Nuclear Physics Question with Solution

JEE Main 2023 (10 Apr Shift 2)

Question

The half life of a radioactive substance is T. The time taken, for disintegrating 78th part of its original mass will be:

Choose an option

Show full solutionCorrect option: B
Correct answer
B3T

Step-by-step explanation

It is given that t12= T.

After disintegration of 78thpart, 18th part is only left.

Using the decay formula,

N=N012tt12

⇒N08=N012tT⇒-ln8=-tTln2⇒3ln2=tTln2⇒t=3T

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About this question

This is a previous-year question from JEE Main 2023, covering the Nuclear Physics chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.