Question

If an electron has orbital angular momentum quantum number $ l=7 $ then it will have an orbital angular momentum equal to:

• A. $\sqrt{56}\left(\frac{h}{2 \pi}\right)$
• B. $57\left(\frac{h}{2 \pi}\right)$
• C. $ 42\left( \frac{h}{2\pi } \right) $
• D. $ 7\left( \frac{h}{2\pi } \right) $

Answer 1

Answer: (A)

$L=\sqrt{l(l+1)} \cdot \frac{h}{2 \pi}$
$=\sqrt{7 \times 8} \frac{h}{2 \pi}$
$=\sqrt{56} \frac{h}{2 \pi}$