Radioactivity

 An α-particle of energy 10 Mev is scattered through 180^o by a fixed uranium nucleus. Calculate the order of distance of the closest approach?

If an α-particle collides head-on with a nucleus, what is its impact parameter?

In which of the following, no change in mass number of the daughter nuclei takes place?
(i) $\alpha$ decay       (ii) $\beta$ decay         (iii) $\gamma$ decay        (iv) Neutron decay

In the chain reaction.

${}_{92}{}^{238}\mathrm{U}⟶\mathrm{Ba}+\mathrm{Kr}+3{}_0{}^1\mathrm{n}+$ energy $\mathrm{E}$

neutrons and energy produced at $\mathrm{n}$ th step will be

Which of the following is electromagentic wave:

${ }^{227}\mathrm{A}\mathrm{c}$ has a half-life of 22 years with respect to radioactive decay. The decay follows two parallel paths: ${ }^{227}\mathrm{Ac}\to \mathrm{ }{ }^{227}\mathrm{T}\mathrm{h}$ and ${ }^{227}\mathrm{Ac}\to { }^{223}\mathrm{F}\mathrm{r}$ . If the percentage of the two daughter nuclides are $2.0$ and $98.0$ , respectively the decay constant (in $\mathrm{y}\mathrm{e}\mathrm{a}{\mathrm{r}}^{-1}$ ) for ${ }^{227}\mathrm{Ac}\to \mathrm{ }{ }^{227}\mathrm{T}\mathrm{h}$ path is closest to

At radioactive equilibrium, the ratio between number of atoms of radioactive elements A and B is $3.1\times {10}^9 :1$. If the half-life period of A is $2\times {10}^{10} yrs,$ then the half-life of B is

How many numbers of neutrons will be present in newly formed compound when two $\mathrm{\alpha }$ particle and one $\mathrm{\beta }$particle are emitted from ${}_{94}^{244}\mathrm{M}$ ?

The number of neutrons accompanying the formation of ${}_{\text{54}}^{\text{139}}\text{Xe}$ and ${}_{\text{38}}^{\text{94}}\text{Sr}$ from the adsorption of a slow neutron by ${}_{\text{92}}^{\text{235}}\text{U}$ followed by nuclear reaction is.

A photon of hard gamma radiation knocks a proton out of $\underset{12}{\overset{24}{}}\text{Mg}$ the nucleus to form.