If \(\frac{N}{Z}\) ratio in a nucleus is smaller than the required value for stability, then:
1. It may emit \(\alpha\text-\)particle.
2. It may emit \(\beta^{+}\) particle.
3. It may go for \(K\) capture.
4. All of the above are possible.

Subtopic:  Types of Decay |
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Determine the energy released in the process:
\({}_{1}^{2}\mathrm{H}+ {}_{1}^{2}\mathrm{H}\rightarrow {}_{2}^{4}\mathrm{He}+Q\)
Given: \(M\left({}_{1}^{2}\mathrm{H}\right)= 2.01471~\text{amu}, M\left({}_{2}^{4}\mathrm{He}\right)= 4.00388~\text{amu}\)
1. \(3.79\) MeV
2. \(13.79\) MeV
3. \(0.79\) MeV 
4. \(23.79\) MeV
Subtopic:  Mass-Energy Equivalent |
 70%
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Consider the following statements:

(I) All isotopes of elements have the same number of neutrons.
(II) Only one isotope of an element can be stable and non-radioactive.
(III) All elements have isotopes.
(IV) All isotopes of carbon can form chemical compounds with oxygen\(\text-16\).

The correct option regarding an isotope is:

1. (III) and (IV) only
2. (II), (III), and (IV) only
3. (I), (II), and (III) only
4. (I), (III), and (IV) only
Subtopic:  Nucleus |
 60%
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When \({}_{3}^{7}\mathrm{Li}\) nuclei are bombarded by protons, and the resultant nuclei are \({}_{4}^{8}\mathrm{Be}\) the emitted particles will be:
1. Neutrons 2. Alpha particles
3. Beta particles 4. Gamma photons
Subtopic:  Types of Decay |
 52%
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If in nuclear reactor using \(\mathrm{U}^{235}\) as fuel, the power output is \(4.8\) MW, the number of fissions per second is:
(Energy released per fission of \(\mathrm{U}^{235}=200\) MeV watts, \(1~\text{eV}= 1.6\times 10^{-19}~\text{J})\)
 
1. \(1.5\times 10^{17}\) 2. \(3\times 10^{19}\)
3. \(1.5\times 10^{25}\) 4. \(3\times 10^{25}\)
Subtopic:  Nuclear Energy |
 71%
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Calculate the \(Q\text-\)value of the nuclear reaction:
\(2~{ }_{6}^{12} \mathrm{C}\rightarrow{ }_{10}^{20} \mathrm{Ne}+{ }_2^4 \mathrm{He}\)
The following data are given:
\(m({ }_{6}^{12} \mathrm{C})=12.000000~\text{amu}\)
\(m({ }_{10}^{20} \mathrm{Ne})=19.992439~\text{amu}\)
\(m({ }_{2}^{4} \mathrm{He})=4.002603~\text{amu}\)
1. \(3.16~\text{MeV}\)
2. \(5.25~\text{MeV}\)
3. \(3.91~\text{MeV}\)
4. \(4.65~\text{MeV}\)

Subtopic:  Mass-Energy Equivalent |
 53%
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A nucleus \({}_{Z}^{A}\mathrm{X}\) emits \(9~\alpha\text-\)particles and \(5~\beta\text-\)particles. The ratio of total protons and neutrons in the final nucleus is:
1. \(\dfrac{(Z - 13)}{\left(A - Z - 23\right)}\) 2. \(\dfrac{\left(Z - 18\right)}{\left(A - 36\right)}\)
3. \(\dfrac{\left(Z - 13\right)}{\left(A - 36\right)}\) 4. \(\dfrac{\left(Z - 13\right)}{\left(A - Z - 13\right)}\)
Subtopic:  Types of Decay |
 59%
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An element \(\mathrm{X}\) decays, first by positron emission, and then two \(\alpha\text-\)particles are emitted in successive radioactive decay. If the product nuclei have a mass number \(229\) and atomic number \(89\), the mass number and the atomic number of element \(\mathrm{X}\) are:
1. \(237,~93\) 
2. \(237,~94\)
3. \(221,~84\)
4. \(237,~92\)

Subtopic:  Types of Decay |
 57%
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What is the respective number of \(\alpha\) and \(\beta\text-\) particles emitted in the following radioactive decay?
\({}_{90}^{200}\mathrm{X}\rightarrow {}_{80}^{168}\mathrm{Y}\)
1. \(6\) and \(8\) 2. \(6\) and \(6\)
3. \(8\) and \(8\) 4. \(8\) and \(6\)   
Subtopic:  Types of Decay |
 84%
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If a proton and anti-proton come close to each other and annihilate, how much energy will be released?

1. \(1.5 \times10^{-10}~\text{J}\) 2. \(3 \times10^{-10}~\text{J}\)
3. \(4.5 \times10^{-10}~\text{J}\) 4. None of these
Subtopic:  Mass-Energy Equivalent |
 54%
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