An electron jumps from the 4th orbit to the 2nd orbit of hydrogen atom. Given the Rydberg's constant R = ${10}^5 {\mathrm{cm}}^{-1}$. The frequency in Hz of the emitted radiation will be 
(a) $\frac{3}{16}\times {10}^5$           (b) $\frac{3}{16}\times {10}^{15}$
(c) $\frac{9}{16}\times {10}^{15}$          (d) $\frac{3}{4}\times {10}^{15}$

An electron in the n = 1 orbit of hydrogen atom is bound by 13.6 eV. If a hydrogen atom is in the n = 3 state, how much energy is required to ionize it 
(1) 13.6 eV                     

(2) 4.53 eV
(3) 3.4 eV                       

(4) 1.51 eV

Which of the following statements about the Bohr model of the hydrogen atom is false 

(1) Acceleration of electron in n = 2 orbit is less than that in n = 1 orbit

(2) Angular momentum of electron in n = 2 orbit is more than that in n = 1 orbit

(3) Kinetic energy of electron in n = 2 orbit is less than that in n = 1 orbit

(4) Potential energy of electron in n = 2 orbit is less than that in n = 1 orbit

Ratio of the wavelengths of first line of Lyman series and first line of Balmer series is

(1) 1: 3                 

(2) 27 : 5

(3) 5 : 27               

(4) 4 : 9

In Bohr's model, the atomic radius of the first orbit is ${\mathrm{r}}_0$, then the radius of the third orbit is
(1) $\frac{{\mathrm{r}}_0}{9}$              

(2) ${\mathrm{r}}_0$
(3) $9{\mathrm{r}}_0$               

(4) $3{\mathrm{r}}_0$

In Bohr model of hydrogen atom, the ratio of periods of revolution of an electron in \(n=2\) and \(n=1\) orbits is:
1. \(2:1\)             
2. \(4:1\)
3. \(8:1\)             
4. \(16:1\)

The first line in the Lyman series has wavelength $\mathrm{\lambda }$. The wavelength of the first line in Balmer series is

(1) $\frac{2}{9}\mathrm{\lambda }$             

(2) $\frac{9}{2}\mathrm{\lambda }$
(3) $\frac{5}{27}\mathrm{\lambda }$           

(4) $\frac{27}{5}\mathrm{\lambda }$

The de-Broglie wavelength of an electron in the first Bohr orbit is 
(1) Equal to one fourth the circumference of the first orbit
(2) Equal to half the circumference of the first orbit
(3) Equal to twice the circumference of the first orbit
(4) Equal to the circumference of the first orbit

Taking Rydberg’s constant ${\mathrm{R}}_{\mathrm{H}}=1.097\times {10}^7 \mathrm{m}$ first and second wavelength of Balmer series in hydrogen spectrum is

(a) 2000 Å, 3000 Å                  (b) 1575 Å, 2960 Å
(c) 6529 Å, 4280 Å                  (d) 6552 Å, 4863 Å