The potential energy and electric field?

Just doing some first year physics for exams, and thought about something I don't understand. A simple dipole in an electric field has a calculable potential energy = -p.E.cos(phi) Where p = the electric dipole moment, E = magnitude of electric field...

Two point charges +3.0x10^-6C and + 6.0x10^-6C are separated by 1.20m in vaccum as inthe Figure 2 below: +3.0x10^-6C M + 6.0x10^-6C I-------------------I----------------I <----------------><-------------> 0.60cm 0.60cm a) Find the resultant...

Two point charges + 4.0x10^-9C and - 4.0x10-9C are placed on a straight line as shown in the Figure 1 below: +4.0x10^-9CA B - 4.0x10-9C -I-----------------I------I----------I… <---------------><--><---------> 20.0cm 10.0cm 1...

I think I know the answer but I'm not 100% sure so help please? :D So I know that for potential energy to be stored in the system, the test charge must be moved against the direction of an electric field because this requires work and this will, then...

At the last conceivable point at which a gravitational field has influence over a body, that body still has its full potential energy -  it may still be pulled toward the center of the field. However, at the very next point away from the field's center...

Is it zero? I think this is trick question. Does a current carrying wire induce an electric field as well as a magnetic field. I calculated the energy density of the magnetic field but the next question asked for the energy density of the electric field...

A parallel-plate air-filled capacitor having area 40 cm^2 and plate spacing 1.0 mm is charged to a potential difference of 600 V. Find (a) the capacitance, (b) the amount of excess charge on each plate, (c) the stored energy, (d) the electric field between...