Question

According to Bohr's theory, the angular momentum of an electron in 5th orbit is

• A. $10h/\pi$
• B. $2.5h/\pi$
• C. $25h/\pi$
• D. $h/\pi$

Answer 1

The correct option is B $2.5h/\pi$

Angular momentum of an electron in $n^{th}$ orbit is given by
$mvr=\frac{nh}{2\pi }$
For $n=5$, we have
Angular momentum of electron $=\frac{5h}{2\pi }=\frac{2.5h}{\pi }$