The half-life of a radioactive nuclide is 100 h. The fraction of original activity that will remain after 150 h would be

In the nuclear emission stated above, the mass number and atomic number of the product Q respectively, are:

The half life of a radioactive substance is 20 minutes. In how much time, the activity of substance drops to \(\displaystyle \left(\frac{1}{16}\right)^{th}\) of its initial value?

In the given nuclear reaction, the element X is :
\(\displaystyle ^{23} _{11} \,Na \rightarrow\,X+e^+ + v\)

A nucleus of mass number of 189 splits into two nuclei having mass number 125 and 64. The ratio of radius of two daughter nuclei respectively is :

A radioactive nucleus \({}^{A}_{z}X\) undergoes spontaneous decay in the sequence
\({}^{A}_{z}X \, \rightarrow \, {}_{z-1}B \, \rightarrow \, {}_{z-3}C \, \rightarrow \, {}_{z-2}D\) where Z is the atomic number of element X. The possible decay particles in the sequence are

A nucleus with mass number 240 breaks into two fragments each of mass number 120, the binding energy per nucleon of unfragmented nuclei is 7.6 MeV while that of fragments is 8.5 MeV. The total gain in the binding energy in the process is

The energy equivalent of 0.5 g of a substance is

When a uraniumisotope \(\displaystyle {}^{235}_92U\) is bombarded with a neutron, itgenerates \(\displaystyle {}^{89}_{36}Kr\), three neutrons and

\(\alpha\)-particle consists of

For a radioactive material, half-life is 10 minutes. If initially there are 600 number of nuclei, the time taken (in minutes) for the disintegration of 450 nuclei is

Radioactive material A has decay constant \(8 \lambda\) and material B has decay constant \(\lambda\). Initially, they have same number of nuclei. After what time, the ratio of number of nuclei of material B to that A will be \(\frac{1}{e}\) ?