Two 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 is .
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Previous year questions with solutions · 2025 – 2026
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Two 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 is .
The energy released when 717.13 kg of 37Li is converted into 24He by proton bombardment is 1032 eV. The value of is . (Nearest integer) (Mass of 37Li=7.0183 u, mass of 24He=4.004 u, mass of proton =1.008 u and 1 u =931 MeV/c2 and Avogadro number =6.0 1023)
The energy released if hydrogen atoms are combined to form 24He is MeV. (Take binding energies per nucleon of 12H and 24He as 1.1 MeV and 7.2 MeV, respectively)
Assuming the experimental mass of 612C as 12 u, the mass defect of 612C atom is MeV/c2. (Mass of proton = 1.00727 u, mass of neutron = 1.00866 u, 1 u = 931.5 MeV/c2 and c is the speed of the light in vacuum).
Two 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 are 5.6 MeV, 7.4 MeV and 6.1 MeV, respectively, then in the process, Mc2= MeV.
The binding energy per nucleon of 20983Bi is MeV. [Take m( 20983Bi) = 208.980388 u, mp = 1.007825 u, mn = 1.008665 u, 1 u = 931 MeV/c2]
An atom 83X is bombarded by shower of fundamental particles and in 10 s this atom absorbed 10 electrons, 10 protons and 9 neutrons. The percentage growth in the surface area of the nucleus is recorded by :
A nucleus has mass number and radius R . Another nucleus has mass number and radius R . If = 8 then R /R is :
Given below are two statements : In the light of the above statements, choose the correct answer from the options given below
The binding energies for the following nuclear reactions are expressed in MeV. 2He3 + 0n1 2He4 + 20 MeV 2He4 + 0n1 2He5 - 0.9 MeV If X3, X4, X5 denote the stability of 2He3, 2He4 and 2He5, respectively, then the correct order is :
Which of the following pair of nuclei are isobars of the element?
The average energy released per fission for the nucleus of 23592U is 190 MeV. When all the atoms of 47 g pure 23592U undergo fission process, the energy released is 1023 MeV. The value of is . (Avogadro Number = 6 1023 per mole)
The minimum frequency of photon required to break a particle of mass 15.348 amu into 4 particles is kHz. [mass of He nucleus = 4.002 amu, 1 amu = 1.66 10-27 kg, h = 6.6 10-34 J s and c = 3 108 m/s]
For a nucleus of mass number A and radius R, the mass density of nucleus can be represented as
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the most appropriate answer from the options given below :
A radioactive material P first decays into Q and then Q decays to non-radioactive material R. Which of the following figure represents time dependent mass of P, Q and R ?
Match the LIST-I with LIST-II Choose the correct answer from the options given below:
Energy released when two deuterons (1H2 ) fuse to form a helium nucleus (2He4 ) is : (Given : Binding energy per nucleon of 1H2 = 1.1 MeV and binding energy per nucleon of 2He4 = 7.0 MeV)
Choose the correct nuclear process from the below options [p : proton, n : neutron, e- : electron, e+ : positron, : neutrino, : antineutrino]