Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main202523 Jan 2025Morning ShiftPhysicsNuclear PhysicsActual

A radioactive nucleus n₂ has 3 times the decay constant as compared to the decay constant of another radioactive nucleus n₁ . If initial number of both nuclei are the same, what is the ratio of number of nuclei of n₂ to the number of nuclei of n₁ , after one half-life of n₁ ?

Options

  1. A1 / 8
  2. B8
  3. C4
  4. D1 / 4

Correct answer

D. 1 / 4

Step-by-step solution

aligned & N ₂= N ₀ e ^ -3 t & ~N ₁= N ₀ e ^ - t & N ₂ ~N ₁ = e ^ -2 t & t _ half lifeofN t & t = 2 _ n 1 & ~N ₀ 2 = N ₀ e ^ - t aligned aligned & t = 2 & t = 2 & = e ^ -2 2 & ~N ₂ ~N ₁ = 1 4 aligned

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 rate of per second. Each decay of X produces energy E₀ , which is utilized to heat a liquid of 2026Two radioactive substances A and B of mass numbers 200 and 212 respectively, shows spontaneous -decay with same Q value of 1 MeV. The ratio of energies of -rays produced by A and B 2026The energy released if hydrogen atoms are combined to form ⁴₂ He is __________ MeV. (Take binding energies per nucleon of ²₁ H and ⁴₂ He as 1.1 MeV and 7.2 MeV, respectively) 2026The energy released when 7 17.13 kg of ⁷₃ Li is converted into ⁴₂ He by proton bombardment is 10³² eV. The value of is _______. (Nearest integer) (Mass of ⁷₃ Li = 7.0183 u, mass of 2026Assuming the experimental mass of ¹²₆C as 12 u , the mass defect of ¹²₆C atom is _______ MeV /c^2 . (Mass of proton = 1.00727 u , mass of neutron = 1.00866 u , 1 u = 931.5 MeV /c^2 2026Two nuclei of mass number 3 combine with another nucleus of mass number 4 to yield a nucleus of mass number 10 . If the binding energy per nucleon for the mass numbers 3 , 4 and 10 2026The binding energy per nucleon of ²⁰⁹₈₃Bi is _______ MeV. [ Take m(²⁰⁹₈₃Bi) = 208.980388 , u, , m_p = 1.007825 , u, , m_n = 1.008665 , u, , 1 , u = 931 , MeV /c^2] 2026A nucleus has mass number and radius R_ . Another nucleus has mass number and radius R_ . If =8 then R_ / R_ is: 2026 Full Nuclear Physics list All JEE Main PYQs