Nuclei practice · Medium

Radio carbon dating is done by estimating in specimen the

For a nuclear to be in critical condition, the value of neutron multiplication factor $k$ must be

Pick out the unmatched pair from the following

Statement I : Energy is released when heavy nuclei undergo fission or light nuclei undergo fusion.

Statement II : For heavy nuclei, binding energy per nucleon increases with increasing Z while for light nuclei it decreases with increasing $\mathrm{Z}$.

Hydrogen bomb is based on which of the following phenomenon

In the given reaction, find value of $Q$ value.

${ }_6 C^{13} \longrightarrow {}_6C^{12}+{ }_0 n^1+(Q-\text {value})$

Given: mass of ${ }_6 C^{13} \Rightarrow x$

mass of ${ }_6 C^{12} \Rightarrow y$

mass of ${ }_0 n^1 \Rightarrow z$

In nuclear fission, the fission reactions proceeds with a projectile. Which of the following suits the best

The binding energy per nucleon of ${O^{16}}$ is $7.97\,\,MeV$ and that of ${O^{17}}$ is $7.75\,\,MeV$. The energy (in $MeV$) required to remove a neutron from ${O^{17}}$ is

The example of nuclear fusion is

In an $\alpha -$ decay, the kinetic energy of $\alpha -$ particle is 48 MeV and Q value of the reaction is 50 MeV. The mass number of the mother nucleus is [assume that daughter nucleus is in ground state]

If $10 \%$ of a material decays in 5 days, then the amount of original material left after 20 days is approximately

How much mass of $U^{235}$ is required per sec to operate the nuclear reactor generating power $100 \mathrm{~kW}$.

Assertion: The nuclear force between two nucleons falls rapidly to zero as their distance is more than a few femtometer.

Reason: Nuclear force is a short range force

${M_n}$ and ${M_p}$ represent mass of neutron and proton respectively. If an element having atomic mass $M$ has $N$-neutrons and $Z$-protons, then the correct relation will be

If half life of radium is $\mathrm{77 }\,\mathrm{days}$. Its decay constant in day will be

The activity of a radioactive sample decreases to one-third of the original value in 9 years. What will be the activity after further 9 years ?

Half-life of radioactive sample, when activity of material initially was $\mathrm{8 }\,\mathrm{counts}$ and after $\mathrm{3}\,\,\mathrm{h}$ it becomes $\mathrm{1 }\,\mathrm{counts}$, is

The ratio of mass densities of nuclei of $^{40}Ca$ and $^{16}O$ is close to

Which of the following is possible in a $\beta^{+}$ decay?

A nucleus decays by ${\mathrm{\beta }^ + }$-emission followed by a $\gamma - \mathrm{emission}$. If the atomic and mass numbers of the parent nucleus are $Z$ and $A$ respectively, the corresponding numbers for the daughter nucleus are respectively

The fraction of the initial number of radioactive nuclei which remain undecayed after half of a half-life of the radioactive sample is

${ }^{65} {Cu}$ will turn into ${ }^{66} {Cu}$ if it is bombarded with

${M_p}$ denotes the mass of a proton and ${M_n}$ that of a neutron. A given nucleus, of binding energy $B$, contains $Z$ protons and $N$ neutrons. The mass $M\left( {N,Z} \right)$ of the nucleus is given by ($c$ is the velocity of light)

It is observed that only $6.25 \%$ of a given radioactive sample is left undecayed after a period of 16 days. What is the decay constant of this sample, in day ${ }^{-1}$ ?

A radioactive substance contains $\mathrm{10000}$ nuclei and its half-life period is $\mathrm{20}$ days. The number of nuclei present at the end of $\mathrm{10}$ days is

Consider the binding energy of ${ }_{17} {Cl}^{35}$ and ${ }_{15} {P}^{31}$ are 287.67 MeV and $262.48 {MeV}$, respectively. Then,

The sodium nucleus ${}_{11}N{a^{23}}$ contains

Nuclear forces are

Half – lives of two radioactive elements $A$ and $B$ are 20 min and 40 min, respectively. Initially, the samples have equal number of nuclei. After 80 min, the ratio of decayed numbers of $A$ and $B$ nuclei will be

Which of the following statements is true for nuclear forces?