Nuclear Physics

At time $t=0$, a material is composed of two radioactive atoms $A$ and $B$, where $N_{A}(0)=2N_{B}(0)$ The decay constant of both kind of radioactive atoms is $\lambda\,$. However, $A$disintegrates to $B$ and…

Activities of three radioactive substances $A,B$ and $C$ are represented by the curves$A,B$ and $C,$in the figure. Then their…

The half life of a radioactive substance is $5$ years. After $x$ years a given sample of the radioactive substance gets reduced to $6.25%$ of its initial value. The value of $x$ is ____

A nucleus with mass number $242$ and binding energy per nucleon as $7.6\mathrm{MeV}$ breaks into two fragment each with mass number $121$. If each fragment nucleus has binding energy per nucleon as $8.1\mathrm{MeV},$…

A freshly prepared radioactive source of half life $2$ hours $30$ minutes emits radiation which is $64$ times the permissible safe level. The minimum time, after which it would be possible to work safely with source,…

A common example of alpha decay is $^{238}_{92}U\rightarrow\,^{234}_{90}\mathrm{Th}+_{2}\mathrm{He}^{4}+Q$ Given: $^{238}_{92}U=238.05060u$ $^{234}_{90}\mathrm{Th}=234.04360u$…

The average energy released per fission for the nucleus of ${ }_{92}^{235} \mathrm{U}$ is 190 MeV. When all the atoms of 47 g pure ${ }_{92}^{235} \mathrm{U}$ undergo fission process, the energy released is $\alpha…

The disintegration energy $Q$ for the nuclear fission of ${ }^{235} \mathrm{U} \rightarrow{ }^{140} \mathrm{Ce}+{ }^{94} \mathrm{Zr}+n$ is ______ $\mathrm{MeV}$. Given atomic masses of ${ }^{235} \mathrm{U}: 235.0439 u…

A radioactive element$X92242$emits two $\alpha\,$-particles, one electron and two positrons. The product nucleus is represented by$YP234$.The value of $P$ is ______?

If three helium nuclei combine to form a carbon nucleus then the energy released in this reaction is _____$\times 10^{-2} \mathrm{MeV}$. (Given $1 \mathrm{u}=931 \mathrm{MeV} / \mathrm{c}^2$, atomic mass of helium…

The energy released when $\dfrac{7}{17.13}$ kg of $^{7}_{3}\text{Li}$ is converted into $^{4}_{2}\text{He}$ by proton bombardment is $\alpha \times 10^{32}$ eV. The value of $\alpha$ is _______. (Nearest integer) (Mass…

$92238A\rightarrow\,90234B+D24+Q$ In the given nuclear reaction, the approximate amount of energy released will be: [Given, mass of$92238A=238.05079\times\,931.5\mathrm{MeV}c^{-2}$,mass…