Question

If the velocity of electron in the first Bhors orbit of H atoms is s$2.19\times {10}^{6}m/s$.calculate the velocity of electron in Bohrs second orbit?

Answer 1

We know that angular momentum remains conserved so $m{v}_1{r}_1=m{v}_2{r}_2$

so $v_2=\frac{r_1}{r_2}{v}_1$

We know that according to Bohr postulate $r_n=n^2{a}_0$, where $a_0$ is radius of ground orbit$=r_1$

So $v_2=\frac{1^2{a}_0}{2^2{a}_0}{v}_1=\frac{v_1}{4}=\frac{2.19}{4}\times {10}^{6}m/s=5.5\times {10}^{5}m/s$