Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main 202228 JulyMorning Shift
Exam
JEE Main
Year
2022
Date
28 July
Shift
Morning Shift
Subject
Physics
Chapter
Nuclear Physics

JEE Main 2022 · 28 July · Morning Shift · Physics · Nuclear Physics

The half life period of a radioactive substance is 60 days. The...

The half life period of a radioactive substance is 6060 days. The time taken for 78\dfrac{7}{8} th of its original mass to disintegrate will be :

Options

  1. A120120 days
  2. B130130 days
  3. C180180 days
  4. D2020 days

Correct answer

C. 180180 days

Step-by-step solution

Given half life period of a radioactive substance is t12=60t\dfrac{1}{2} = 60 days.

Here, 78th\dfrac{7}{8}th of radioactive substance disintegrates means 18th\dfrac{1}{8}th remains or (12)3{\left(\dfrac{1}{2}\right)}^{3}.

∴3∴ 3 half lives =3×60=180days= 3 \times 60 = 180days

Practice Nuclear Physics on Quantrex Academy →

More from Nuclear Physics

A nuclear reactor starts producing a radioactive nuclide X from t = 0 , at a constant… JEE Advanced 2026Two radioactive substances A and B of mass numbers 200 and 212 respectively, shows… JEE Main 2026The energy released if hydrogen atoms are combined to form ^ 4 _ 2 He is __________ MeV.… JEE Main 2026The energy released when (7)/(17.13) kg of ^ 7 _ 3 Li is converted into ^ 4 _ 2 He by… JEE Main 2026Assuming the experimental mass of ^ 12 _ 6 C as 12 u , the mass defect of ^ 12 _ 6 C atom… JEE Main 2026Two nuclei of mass number 3 combine with another nucleus of mass number 4 to yield a… JEE Main 2026The binding energy per nucleon of ^ 209 _ 83 Bi is _______ MeV. [Take m(^ 209 _ 83 Bi) =… JEE Main 2026A nucleus has mass number α and radius R_ α . Another nucleus has mass number β and… JEE Main 2026 Full Nuclear Physics list All JEE Main PYQs