Question

The momentum of an electron revolving in $n ^{\text {th }}$ orbit is given by : (Symbols have their usual meanings)

• A. $\frac{ nh }{2 \pi r }$
• B. $\frac{ nh }{2 r }$
• C. $\frac{n h}{2 \pi}$
• D. $\frac{2 \pi r }{ nh }$

Answer 1

Answer: (A)

Angular momentum is integral multiple of $\frac{ h }{2 \pi} mvr =\frac{ nh }{2 \pi}$
So momentum mv $=\frac{ nh }{2 \pi r }$