Question

Velocity of electron in $2^{nd}$ orbit of $H{e}^{+}$ is

• A. $2.18\times {10}^{3}m/s$
• B. $2.18\times {10}^{6}m/s$
• C. $4.36\times {10}^{6}m/s$
• D. $4.36\times {10}^{3}m/s$

Answer 1

The correct option is B $2.18\times {10}^{6}m/s$

$\because v_n=2.18\times {10}^6\times \frac{Z}{n}m/s$
$=2.18\times {10}^6\times \frac{2}{2}$
$=2.18\times {10}^{6}m/s$