Nuclei practice · Mixed difficulty

The decay constant, for a given radioactive sample, is 0.3465 day $^{-1}$. What percentage of this sample will get decayed in a period of 4 years ?

Which one of the following is a possible nuclear reaction?

The approximate nuclear radius is proportional to ($A$ is the mass number and $Z$ the atomic number)

In the given nuclear reaction ${ }_4^9 \mathrm{Be}+{ }_2^4 \mathrm{He} \rightarrow{ }_6^{12} \mathrm{C}+\mathrm{X}$. $\mathrm{X}$ represents

The binding energies per nucleon for a deuteron and an $\alpha \mathrm{ - }$ particle are ${x_1}\,\,\,\mathrm{and}\,\,\,\,\,{x_2}$ respectively. What will be the energy Q released in the reaction
${}_1{H^2} + {}_1{H^2} \to {}_2H{e^4} + Q$

The binding energy of nucleus is a measure of its

Heavy water is used in a nuclear reactor to

If the mass of a radioactive sample is doubled, the activity of the sample and the disintegration constant of the sample are respectively

From the statements given below:
(A) The angular momentum of an electron in $n^{\text {th}}$ orbit is an integral multiple of $h$.
(B) Nuclear forces do not obey inverse square law.
(C) Nuclear forces are spin dependent.
(D) Nuclear forces are central and charge independent.
(E) Stability of nucleus is inversely proportional to the value of packing fraction.
Choose the correct answer from the options given below:

Which of the following processes represents a $\mathrm{\gamma }$-decay?

The fussion process is possible at high temperatures, because at higher temperatures

If mass equivalent to one mass of proton is completely converted into energy then energy produced is (MeV)

$\mathrm{1}$ curie represents

Assertion: Mass defect in nuclear reactions is less than $1 \%$.

Reason: In nuclear reaction, change in BE/N is generally less than $1\%$.

Radioactive decay will occur as follows

$\begin{aligned} & { }_{86}^{22} {Rn} \rightarrow{ }_{84}^{216} {PO}+{ }_2^5 {He} \text { half life }=55 {~s} \\ & { }_{84}^{216} {Po} \rightarrow{ }^{212} {~Pb}+{ }_2^4 {He} \text { half life }=0.66 {~s} \\ & { }_{82}^{82} {~Pb} \rightarrow{ }_{82}^{212} {BL}+\lambda^{\circ} e \text { Half life }=10.6 {~h} \end{aligned}$

If a certain mass of radon $({Rn}=220)$ is allowed to decay in a certain container; then after 5 minutes the element with the greater mass will be

For a nuclear reactor to run in critical condition the reproduction factor ${k}$ should be

The radioactivity of a certain material drops to $\frac{1}{{16}}$ of the initial value in $\mathrm{2}\,\,\mathrm{h}$. The half-life of this radio nuclide is

The $Q - {\text{value}}$ of a nuclear reaction and kinetic energy of the projectile particle, ${K_p}$ are related as:

Sun maintains its shining because of the

In a sample of radioactive material, what percentage of the initial number of active nuclei will decay during one mean life

In a radioactive reaction ^ ₉₂X²³² → ₈₂X²⁰⁴${^\,_{92}}{X^{232}}{ \to _{82}}{X^{204}}$
the number of $\mathrm{\alpha }$-particles emitted is

What are the respective number of $\alpha$ and $\beta^-$ particles emitted in the following radioactive decay?
$_{90}^{200}X \to \,_{82}^{172}Y$

Statement-1: In negative $\beta$-decay electron is emitted from nucleus, but electron cannot reside inside the nucleus.
Statement-2: Electron experience strong nuclear force.

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

Statement-I: Heavy water absorbs neutrons more efficiently than normal water.

Statement-II: Heavy water has more molecular mass than normal water.

Statement-I: In reactors, light nuclei called modertors are provided along with the fissionable nuclei for slowing down fast neutrons.

Statement-II: In an elastic collision with hydrogen the neutron almost comes to rest and proton carries away the energy.

A radioactive substance has an average life of $\mathrm{5}\,\mathrm{h}$. In a time of $\mathrm{5}\,\mathrm{hours}$

A radioactive substance of half-life 6 min is placed near a Geiger counter which is found to resister $\mathrm{1024}$ particles per minute. How many particles per minute will it register after $\mathrm{42}\,\mathrm{ min}$ ?

If the binding energy per nucleon of deutron is $1.115\,\,\mathrm{MeV}$, its mass defect in atomic mass unit is

If $M(A ; Z), M_p$ and $M_n$ denote the masses of the nucleus ${ }_{\mathrm{Z}}^{\mathrm{A}} \mathrm{X}$, proton and neutron respectively in units of $\mathrm{u}(1 \mathrm{u}=$ $931.5 \mathrm{~MeV} / \mathrm{c}^2$ ) and $\mathrm{BE}$ represents its bonding energy in $\mathrm{~MeV}$, then