Question

Calculate the number of waves made by a Bohr electron in the $2^{nd}$ excited state of hydrogen atom$?$

• A. $1$
• B. $2$
• C. $3$
• D. $4$

Answer 1

The correct option is C $3$

When electron waves are in phase,
$2\pi r=n\lambda$
Where, $n$ represents the number of waves made by the electron as well as the orbit number.
Since, $n=3$ for $2^{nd}$ excited state.
$\therefore \text{number of waves made by electron}=3$