Atomic Energy Levels

Q. According to Bohr's theory of the hydrogen atom, the total energy of the hydrogen atom with its electron revolving in the $n^{th}$ stationary orbit is proportional to

1. $n$
2. $n^2$
3. $\frac{1}{n}$
   
4. $\frac{1}{n^2}$

Q. A $p$-type semiconductor has acceptor level $57\text{meV}$ above the valence band. Find the maximum wavelength of light which can create a hole.

1. $2.18\times {10}^{-5}\text{m}$
2. $4.36\times {10}^{-3}\text{m}$
3. $2.18\times {10}^{-3}\text{m}$
4. $4.36\times {10}^{-5}\text{m}$

Q. According to Bohr's theory of the hydrogen atom, the total energy of the hydrogen atom with its electron revolving in the $n^{th}$ stationary orbit is proportional to

1. $n$
2. $n^2$
3. $\frac{1}{n}$
   
4. $\frac{1}{n^2}$