Q. No.We are given the following atomic masses:
\({ }_{92}^{238} \mathrm{U}=238.05079~\text{u},{ }_2^4 \mathrm{He}=4.00260~\text{u} \\ { }_{90}^{234} \mathrm{Th}=234.04363~\text{u},{ }_1^1 \mathrm{H}=1.00783~\text{u}\\ { }_{91}^{237} \mathrm{~Pa}=237.05121~\text{u} \)
Here the symbol Pa is for the element protactinium \((Z=91)\).
Then:
1.
\({}_{92}^{238}\mathrm{U}\) can not spontaneously emit a proton.
2.
\({}_{92}^{238}\mathrm{U}\) can spontaneously emit a proton.
3.
The \(Q\text-\)value of the process is negative.
4.
Both (1) and (3) are correct.
\({ }_{92}^{238} \mathrm{U}=238.05079~\text{u},{ }_2^4 \mathrm{He}=4.00260~\text{u} \\ { }_{90}^{234} \mathrm{Th}=234.04363~\text{u},{ }_1^1 \mathrm{H}=1.00783~\text{u}\\ { }_{91}^{237} \mathrm{~Pa}=237.05121~\text{u} \)
Here the symbol Pa is for the element protactinium \((Z=91)\).
Then:
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. \(54 ~\text{MW}\)
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. | \(p \rightarrow n+e^{+}+\nu\) |
We are given the following atomic masses:
\({ }_{92}^{238} \mathrm{U}=238.05079~\text{u},{ }_2^4 \mathrm{He}=4.00260~\text{u} \\ { }_{90}^{234} \mathrm{Th}=234.04363~\text{u},{ }_1^1 \mathrm{H}=1.00783~\text{u}\\ { }_{91}^{237} \mathrm{~Pa}=237.05121~\text{u} \)
Here the symbol \(\mathrm{Pa}\) is for the element protactinium \((Z=91)\).
The energy released during the alpha decay of \({}^{238}_{92}\mathrm{U}\) is:
1. \(6.14~\text{MeV}\)
2. \(7.68~\text{MeV}\)
3. \(4.25~\text{MeV}\)
4. \(5.01~\text{MeV}\)
| 1. | \(\alpha\text-\)decay. |
| 2. | \(\beta^{-}\text-\)decay. |
| 3. | \(\beta^{+}\text{-}\)decay. |
| 4. | \(K\text{-}\)electron capture. |
1. An electric force
2. Weak nuclear force
3. Strong nuclear force
4. Gravitational force
| 1. | is only attractive force. |
| 2. | is only repulsive force. |
| 3. | maybe attractive or repulsive in nature depending on the distance. |
| 4. | is a central force. |
1. \(4.4~\text{fm}\)
2. \(7~\text{fm}\)
3. \(22~\text{fm}\)
4. \(17.6~\text{fm}\)
| 1. | \( \mathrm{F}_{\mathrm{pp}}<\mathrm{F}_{\mathrm{pn}}<\mathrm{F}_{\mathrm{nn}} \) | 2. | \( \mathrm{F}_{\mathrm{pn}}>\mathrm{F}_{\mathrm{pp}}>\mathrm{F}_{\mathrm{nn}} \) |
| 3. | \( \mathrm{F}_{\mathrm{pp}}>\mathrm{F}_{\mathrm{pn}}>\mathrm{F}_{\mathrm{nn}} \) | 4. | \(\mathrm{F}_{\mathrm{pp}}=\mathrm{F}_{\mathrm{pn}}=\mathrm{F}_{\mathrm{nn}}\) |
\(A\rightarrow B\rightarrow C\)
If each of the decays can be either \(\alpha\) or \(\beta^-\), then which of the following values of \(Z_C\) is possible? (\(Z_C\) & \(Z_A\) are the atomic numbers of \(C\) & \(A\).)
1. \(Z_A+2\)
2. \(Z_A-1\)
3. \(Z_A-4\)
4. Any of the above
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