Nuclear Physics and Radioactivity Questions

A certain mass of Hydrogen is changed to Helium by the process of fusion. The mass defect in fusion reaction is 0.02866 u. The energy liberated per u is : (given 1u = 931 MeV)

If radius of the 2713Al nucleus is taken to be RAl then the radius of 12553Te nucleus is nearly :

Radioactive material 'A' has decay constant '8 λ' and material 'B' has decay constant 'λ'. Initially they have same number of nuclei. After what time, the ratio of numbe...

In a radioactive decay chain, T90232h nucleus decays to P82212b nucleus. Let Nα and Nβ be the number of α and -β particles, respectively, emitted in this decay process. Which of the following...

The half life of a radioactive isotope ′X′ is 20 years. It decays to another element ′Y′ which is stable. The two elements ′X′ and ′Y′ were found to be ...

The activity of radioactive sample is measured as 9750 counts per minute at t = 0 and as 975 counts per minute at t = 5 minutes, and decay constant is approximately :

A radio isotope X with a half life 1.4 × 109 years decays of Y which is stable. A sample of the rock from a cave was found to contain X and Y in the ratio 1 : 7. The age of the rock is...

When a β−-particle is emitted from a nucleus, the neutron-proton ratio :

A radioactive nucleus of mass M emits a photon of frequency and the nucleus recoil. The recoil energy will be

The half-life ofg the radioactive radon is 3.8 days. The time, at the end of which 1/20t of the radon sample will remail undecayed, is (given log10e = 0.4343)

Beta rays emitted by a radioactive material are

The equation ; 411H → 24He2 + 2e- + 26MeV represents

During a negative beta decay

During a nuclear fusion reaction

freshly prepared radioactive source of half-life 2 h emits radiation of intensity which is 64 times of the permissible safe level. The minimum time after which it would be possible work safely with th...

he decay constant of radioactive sample is λ. The half-life and mean-life of the sample are respectively given by

A star initially has 104 deutetron. It produces energy via the processes 1H2 + 1H2 → 1H3 + p and 1H2 + 1H3 → 2He4 + n. If the average power radiated by the star is 1016 W, the deuteron sup...

Fast neutrons can easily be slowed down by

Consider α- particle, β - particle and γ- particle each having an energy of 0.5 MeV. In increasing order of penetrating powers, the radiations are

The half-life of $^{131}\text{I}$ is 8 days. Given a sample of $^{131}\text{I}$ at time $t = 0$, we can assert that