At a distance d from a point charge Q, the energy density in its electric field is u. If we now go to a distance d/2 from the charge, what is the energy density at the new location?

Question

Quizplus · Accepted Answer

The energy density of an electric field due to a point charge is proportional to the square of the electric field, which is inversely proportional to the square of the distance from the charge. Therefore, halving the distance increases the energy density by a factor of $ (d/d/2)^2 = 4^2 = 16 $.

At a Distance D from a Point Charge Q, the Energy