Question

The circumference of the second orbit of electron in hydrogen atom os 400nm, the de-Broglie wavelength of electron corresponding to the circumference of same orbit is 200 nm. Number of waves made by an electon is

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

The correct option is B 2

Number of waves made by electron$\left(n\right)=\frac{\text{circumference}}{\text{wavelength}}$
$n=\frac{400}{200}nm$
$n=2$