Nuclei practice · Mixed difficulty

Assertion: ${ }_1^3 {H}$ isotope does not undergo fusion of the type ${ }_1^3 {H}+{ }_1^2 {H} \rightarrow$ as it is rarely found in nature.
Reason: ${ }_1^3 {H}$ has half life of $> >12$ years.

The atomic mass of ${ }_6 \mathrm{C}^{12}$ is $12.000000 \mathrm{~u}$ and that of ${ }_6 \mathrm{C}^{13}$ is $13.003354 \mathrm{~u}.$ The required energy to remove a neutron from ${ }_6 \mathrm{C}^{13},$ if mass of neutron is $1.008665 \mathrm{~u},$ will be:

${F_{pp}},{F_{nn}}\,\,\mathrm{and}\,\,{F_{np}}$ are the nuclear forces between proton-proton, neutron-neutron and neutron-proton respectively. Then relation between them is

A nucleus disintegrates into two nuclear parts which have their velocities in the ratio $\mathrm{2:1}$. The ratio of their nuclear sizes will be

Curie is a unit of

In gamma ray emission from a nucleus

Atomic reactor is based on

For thorium $A = 232$,$Z = 90$ at the end of some radioactive disintegration we obtain an isotope of lead with $A = 208$ and $Z = 82$, then the number of emitted $\mathrm{\alpha }\,\,\mathrm{and}\,\,\mathrm{\beta }$ particles are

In which of the following decay, the element does not change

Identify the pair of physical quantities that have same dimensions:

Statement-I: Positive values of packing fraction implies a large value of binding energy.

Statement-II : The difference between the mass of the nucleus and the mass number of the nucleus is called packing fraction.

An electron is

A radioactive nucleus can decay simultaneously by two different processes which have decay constant ${\lambda _1}\,\,\mathrm{and}\,\,{\lambda _2}$.The effective decay constant of the nuclide is $\lambda ,$ where

${U^{238}}$ decays into $T{h^{234}}$ by the emission of an $\alpha -$ particle. There follows a chain of further radioactive decays, either by $\alpha -$ decay or by $\beta -$ decay. Eventually a stable nuclide is reached and after that, no further radioactive decay is possible. Which of the following stable nuclides is the end product of the ${U^{238}}$ radioactive decay chain

From a newly formed radioactive substance (Half life $2\,\,hours$), the intensity of radiation is $\mathrm{64}$ times the permissible safe level. The minimum time after which work can be done safely from this source is

A radioactive element forms its own isotope after $\mathrm{3}$ consecutive disintegrations. The particles emitted are

The radioactive nucleus $_7{N^{13}}$ decays to $_6{C^{13}}$ through the emission of

An observer $A$ sees an asteroid with a radioactive element moving by at a speed $= 0.3\,\,c$ and measures the radioactivity decay time to be ${T_A}$. Another observer $B$ is moving with the asteroid and measures its decay time as ${T_B}$. Then ${T_A}$ and ${T_B}$ are related as below

An element of mass $\mathrm{M}$ has $\mathrm{Z}$ protons and $\mathrm{N}$ neutrons. Masses of proton and neutron are $m_p$ and $m_n$ respectively. Choose the correct relation among following options

The momentum of an electron revolving in $n^{\text {th }}$ orbit is given by: (Symbols have their usual meanings)

Given the masses of various atomic particles ${m_p} = 1.0072\,u,\,\,\,\,{m_n} = 1.0087\,\,u,\,\,\,\,{m_e} = 0.000548\,\,u,\,\,\,\,{m_{\bar v}} = 0,\,\,\,\,{m_d} = 2.0141\,\,u,$ Where $p$ = proton, $n$ = neutron, $e$ = electron $\bar v =$ antineutrino and $d$ = deuteron. Which of the following process is allowed by momentum and energy conservation?

Which can pass through $20\,\,cm$ thickness of the steel

A nucleus at rest disintegrates into two smaller nuclei with their masses in the ratio of $2: 1$. After disintegration they will move :-

Radio carbon dating is done by estimating in specimen the

After one alpha particle emission and one $\beta$-particle emission from a nucleus

In a material medium, when a positron meets an electron both the particles annihilate leading to the emission of two gamma ray photons. This process forms the basis of an important diagnostic procedure called

Minimum energy required to take out the only one electron from ground state of $H{e^ + }$ is

The particle emitted in the decay of ${ }_{92}^{238} \mathrm{U}$ to ${ }_{92}^{234} \mathrm{U}$

If the binding energies of a deuteron and an alpha particle are $\mathrm{1}\mathrm{.125}\,\,\mathrm{MeV}$ and $\mathrm{7}\mathrm{.2}\,\,\mathrm{MeV}$, respectively , then the more stable of the two is

$\mathrm{1}$ curie represents