Let \({N_B}\)  the number of \(\beta\) particles emitted by a gram of \({Na^{24}}\) radioactive nuclei (half-life \(=15\) hrs) in \(7.5\) hours, \({N_\beta}\) is close to:
(Avogadro number \(=6.023\times10^{23}/\text{g}.\) mole)
1. \(6.2\times10^{21}\)
2. \(7.5\times10^{21}\)
3. \(1.25\times10^{22}\)
4. \(1.75\times10^{22}\)
Subtopic:  Types of Decay |
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Two deuterons undergo nuclear fusion to form a helium nucleus. The energy released in this process is:
(given binding energy per nucleon for deuteron \(=1.1~\text{MeV}\) and for helium \(=7.0~\text{MeV})\) 
1. \(19.2~\text{MeV}\)
2. \(23.6~\text{MeV}\)
3. \(26.9~\text{MeV}\)
4. \(13.9~\text{MeV}\)
Subtopic:  Nuclear Binding Energy |
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Imagine that a reactor converts all given mass into energy and that it operates at a power level of \(10^{9}~\text{W}.\) The mass of the fuel consumed per hour in the reactor will be:
(velocity of light, \(c=3\times10^8~\text{m/s}) \)
1. \(4\times10^{-2}~\text{gm} \)
2. \(6.6\times10^{-5}~\text{gm} \)
3. \(0.8~\text{gm} \)
4. \(0.96~\text{gm} \)
Subtopic:  Mass-Energy Equivalent |
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A solution containing active cobalt \(\frac{60}{27}~\text{Co}\) having activity of \(0.8 \mu~ \text {Ci} \) and decay constant \(\lambda \) is injected into an animal's body. If \(1~ \text{cm}^3\) of blood is drawn from the animal's body after \(10 ~\text{hr}\) of injection, the activity found was \(300\) decays per minute. What is the volume of blood that is flowing in the body?
(\(1~\text{Ci} = 3.7 \times 10^{10} \) decays per second and at \(t = 10 ~\text{hr},~~~ e^{-\lambda t} = 0.84 )\)
1. \(4 ~\text{liters}\)
2. \(6 ~\text{liters} \)
3. \(5 ~\text{liters}\)
4. \(7 ~\text{liters}\)
Subtopic:  Types of Decay |
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The ratio of the mass densities of the nuclei \({ }^{40} \mathrm{Ca}\) and \({ }^{16} \mathrm{O}\) is close to:

1. \(0.1\) 2. \(2\)
3. \(5\) 4. \(1\)
Subtopic:  Nucleus |
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In a reactor, \(2\) kg of \({ }_{92} \mathrm{U}^{235}\) fuel is fully used up in \(30\) days. The energy released per fission is \(200\) MeV. Given that the Avogadro number, \(\mathrm{N}=6.023 \times 10^{26}\) per kilo mole and \(1~ \mathrm{eV}=1.6 \times 10^{-19}~\text{J}\). The power output of the reactor is close to:
1. \(125 ~\text{MW}\)
2. \(60~\text{MW}\)
3. \(35 ~\text{MW}\)
4. \(54 ~\text{MW}\)

Subtopic:  Mass-Energy Equivalent |
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The radius \(R\) of a nucleus of mass number \(A\) can be estimated by the formula \({R}=\left(1.3 \times 10^{-15}\right) A^{1 / 3} ~\text{m}\) , It follows that the mass density of a nucleus is of the order of:  \(\left(M_{\text {propt. }}=M_{\text {neut. }}=1.67 \times 10^{-27} ~\text{kg}\right)\)
1. \( 10^{10}~ \text{kg}\text{m}^{-3} \)
2. \( 10^{24} ~\text{kg} \text{m}^{-3} \)
3. \( 10^{17} ~\text{kg} \text{m}^{-3} \)
4. \( 10^{3} ~\text{kg} \text{m}^{-3} \)

Subtopic:  Nucleus |
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Given that the masses of a proton, a neutron, and the nucleus of \({ }_{50}^{120} \mathrm{Sn}\) are \(1.00783~\mathrm{u},\) \(1.00867~\mathrm{u},\) and \(119.902199~ \mathrm{u},\) respectively. The binding energy per nucleon of the tin nucleus is: \((1~\text{u}=931~\text{Mev})\)

1. \(9~\text{MeV}\) 2. \(8.5~\text{MeV}\)
3. \(8.0~\text{MeV}\) 4. \(7.5~\text{MeV}\)
Subtopic:  Nuclear Binding Energy |
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You are given that mass of \({ }_a^7 \mathrm{Li}=7.0160 ~\text{u}\) Mass of \({ }_2^4 \mathrm{He}=4.0026 ~\text{u}\) and Mass of \({ }_1^1 \mathrm{H}=1.0079 ~\text{u}\)
When \(20~\text{g}\) of \({ }_a^7 \mathrm{Li}\) is converted into \({ }_2^4 \mathrm{He}\) By proton capture, the energy liberated, (in kWh), is: 
[Mass of nucleon = \(1~\text{GeV/c}^2\)]
1. \( 1.33 \times 10^6 \)
2. \( 8 \times 10^6 \)
3. \( 6.82 \times 10^5 \)
4. \( 4.5 \times 10^5 \)

Subtopic:  Nuclear Energy |
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Given the following particle masses:
\(m_p=1.0072~\text{u}\) (proton)
\(m_n=1.0087~\text{u}\) (neutron)
\(m_e=0.000548~\text{u}\) (electron)
\(m_\nu=0~\text{u}\) (antineutrino)
\(m_d=2.0141~\text{u}\) (deuteron)
Which of the following processes is allowed, considering the conservation of energy and momentum?

1. \(n+p \rightarrow d+\gamma\)
2. \(e^{+}+e^{-} \rightarrow \gamma\)
3. \(n+n\rightarrow \text{}\) deuterium atom (electron bound to the nucleus)
4. \(p \rightarrow n+e^{+}+\nu\)
Subtopic:  Mass-Energy Equivalent |
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