find the energy e of electric field of a point charge q is an empty half-space which is bounded by a plane located at a distance from the charge
Hello candidate,
The electric energy between the two charged particles one of charge q and other a charged plate in an empty spaceis given by the electric force acting between the two surfaces multiplied by the distance between them.
So, the expression of electrical energy will n equal to kq^2/r, where r is taken to be the distance between the two charged particles.
Hope this answer was helpful!!