Question

According to Bohr's theory, the expressions for the kinetic and potential energy of an electron revolving in an orbit is given respectively by.

• A. $+ \frac{e^{2}}{8\pi\varepsilon_{0}r}$and $- \frac{e^{2}}{4\pi\varepsilon_{0}r}$
• B. $+ \frac{8\pi\varepsilon_{0}e^{2}}{r}$and$- \frac{4\pi\varepsilon_{0}e^{2}}{r}$
• C. $- \frac{e^{2}}{8\pi\varepsilon_{0}r}$and $- \frac{e^{2}}{4\pi\varepsilon_{0}r}$
• D. $+ \frac{e^{2}}{8\pi\varepsilon_{0}r}$and $+ \frac{e^{2}}{4\pi\varepsilon_{0}r}$

Answer 1

Answer: (A)

$+ \frac{e^{2}}{8\pi\varepsilon_{0}r}$and $- \frac{e^{2}}{4\pi\varepsilon_{0}r}$

Answer 2

P.E.$= - \frac{ke^{2}}{r} = - \frac{e^{2}}{4\pi\varepsilon_{0}r}$; K.E.$= - \frac{1}{2}(\text{P.E.}) = \frac{e^{2}}{8\pi\varepsilon_{0}r}$