Q. No.In Bohr's model if the atomic radius of the first orbit is \(r_0\), then what will be the radius of the third orbit?
1.
\(\dfrac{r_0}{9}\)
2.
\(r_0\)
3.
\(9r_0\)
4.
\(3r_0\)
| 1. | \(\dfrac{25}{9}\) | 2. | \(\dfrac{17}{6}\) |
| 3. | \(\dfrac{9}{5}\) | 4. | \(\dfrac{4}{3}\) |
| 1. | \(\dfrac{25}{9}\) | 2. | \(\dfrac{17}{6}\) |
| 3. | \(\dfrac{9}{5}\) | 4. | \(\dfrac{4}{3}\) |
\((a_0\)
| 1. | \(E_0=-27.2 ~\text{eV};~r_0={a}_0 / 2\) |
| 2. | \(E_0=-27.2 ~\text{eV}; ~r_0={a}_0\) |
| 3. | \(E_0=-13.6~\text{eV} ; ~r_0={a}_0 / 2\) |
| 4. | \(E_0=-13.6 ~\text{eV}; ~r_0={a}_0\) |
1. \(r_n \propto n\)
2. \(r_n \propto\frac{1}{n}\)
3. \(r_n\propto n^2\)
4. \(r_n \propto\frac{1}{n^2}\)
| 1. | its potential energy increases and kinetic energy decreases. |
| 2. | its potential energy decreases and kinetic energy increases. |
| 3. | both kinetic energy and potential energy increase. |
| 4. | both kinetic energy and potential energy decrease. |
A beam of fast-moving alpha particles was directed towards a thin film of gold. The parts \(A', B',\) and \(C'\) of the transmitted and reflected beams corresponding to the incident parts \(A,B\) and \(C\) of the beam, are shown in the adjoining diagram. The number of alpha particles in:
| 1. | \(B'\) will be minimum and in \(C'\) maximum |
| 2. | \(A'\) will be the maximum and in \(B'\) minimum |
| 3. | \(A'\) will be minimum and in \(B'\) maximum |
| 4. | \(C'\) will be minimum and in \(B'\) maximum |
In the \(n^{th}\) orbit, the energy of an electron is \(E_{n}=-\frac{13.6}{n^2} ~\text{eV}\) for the hydrogen atom. What will be the energy required to take the electron from the first orbit to the second orbit?
1. \(10.2~\text{eV}\)
2. \(12.1~\text{eV}\)
3. \(13.6~\text{eV}\)
4. \(3.4~\text{eV}\)
In a Rutherford scattering experiment when a projectile of charge \(Z_1\) and mass \(M_1\) approaches a target nucleus of charge \(Z_2\)
and mass \(M_2\) the distance of the closest approach is \(r_0.\) What is the energy of the projectile?
| 1. | Directly proportional to \(M_1 \times M_2\) |
| 2. | Directly proportional to \(Z_1Z_2\) |
| 3. | Inversely proportional to \(Z_1\) |
| 4. | Directly proportional to the mass \(M_1\) |
1. \(-13.6~\text{eV}\)
2. \(-27.2~\text{eV}\)
3. \(-54.4~\text{eV}\)
4. \(-6.8~\text{eV}\)
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