Consider the following electronic energy level diagram of H-atom: Photons associated with the shortest and longest wavelengths would be emitted from the atom by the transitions labeled-

1. B and C respectively

2. C and A respectively

3.  C and D respectively

4. A and C respectively

The wavelength of the spectral line that corresponds to a transition in a hydrogen atom from n=10 to ground state would be and in which part of the electromagnetic spectrum this line lies?

1. 92.25 nm, ultraviolet

2. 92.25 nm, infrared

3. 86.95 nm, ultraviolet

4. 97.65 nm, ultraviolet

The angular momentum of an electron in the hydrogen atom is 4h/2$\mathrm{\pi }$. Kinetic energy of this electron is:

1. 4.35 eV

2. 1.51 eV

3. 0.85 eV

4. 13.6 eV

In a hydrogen atom, the electron makes a transition from n=2 to n=1. The magnetic field produced by the circulating electron at the nucleus:

1. decreases 16 times

2. increases 4 times

3. decreases 4 times

4. increases 32 times

Angular momentum (L) and radius (r) of a hydrogen atom are related as:

1. Lr = constant

2. $L{r}^2$=constant

3. $L{r}^4$=constant

4. None of these

An electron in the ground state of hydrogen has an angular momentum $L_1$ and an electron in the first excited state of lithium has an angular momentum $L_2$. Then

1. $L_1=L_2$

2. $L_1=4L_2$

3. $L_2=2L_1$

4. $L_1=2L_2$

The voltage applied to an X-ray tube is 18 kV. The maximum mass of photon emitted by the X-ray tube will be: 

1. $2\times {10}^{-13} \mathrm{kg}$

2. $3.2\times {10}^{-36 }\mathrm{kg}$

3. $3.2\times {10}^{-32} \mathrm{kg}$

4. $9.1\times {10}^{31} \mathrm{kg}$

The force acting on the electron in a hydrogen atom depends on the principal quantum number as:

1. $\mathrm{F}\propto {\mathrm{n}}^2$

2. $\mathrm{F} \propto \frac{1}{{\mathrm{n}}^2}$

3. $\mathrm{F} \propto {\mathrm{n}}^4$

4. $\mathrm{F} \propto \frac{1}{{\mathrm{n}}^4}$

The ratio (in SI units) of magnetic dipole moment to that of the angular momentum of an electron of mass m kg and charge e coulomb in Bohr's orbit of hydrogen atom is:

1. $\frac{e}{2m}$

2. $\frac{e}{m}$

3. $\frac{2e}{m}$

4. none of these 

If the first excitation potential of the hydrogen-like atom is V volt, then the ionization energy of this atom will be:

1. V electron volt

2. $\frac{2\mathrm{V}}{4}\mathit{ }$electron volt
3. $\frac{4\mathrm{V}}{3}$ electron volt

4. cannot be calculated by the given information