Question

The kinetic energy of an electron revolving around a nucleus will be

• A. four times of its P.E.
• B. twice of its P. E.
• C. equal to its P. E.
• D. half of its P. E.

Answer 1

Answer: (D)

K.E. of electron $=\frac{13.6 Z ^{2}}{n^{2}} eV$
P.E. of electron $=\frac{2 \times 13.6 Z ^{2}}{n^{2}} eV$
$\therefore $ K.E. of electron $=\frac{1}{2} \times$ P.E. of electron