Question

If the radius of 3rd Bohr's orbit of an H-like atom is 477 pm, then what will be the radius of 4th Bohr's orbit of the same atom?

Answer 1

$\frac{r_4}{r_3}=\frac{4^2{r}_0}{3^2{r}_0}\Rightarrow r_4=\frac{16}{9}{r}_3=\frac{16}{9}\times 477=848pm$