Physics - Modern Physics Question with Solution | TestHub

The potential energy (PE) of an electron in an orbit is related to its total energy (E) by the equation $PE=2E$.

Given that the total energy of the electron in the $n=3$ state is $E$,

its potential energy is simply $2E$.

The potential energy is negative, but the question asks for the magnitude with the proper sign, and since the total energy E is negative, the potential energy is twice that value. Therefore, $PE=2E$.