Potential difference is the work done in moving a positive test charge from infinity to the point in question.
Voltage is an expression of PD. (Joules / Coulomb)
Say that a capacitor has a PD of 5 Volts. The work in moving a positive test charge from the positive plate to the negative plate is -5 Joules/Coulomb or -5 volt. (At the positive plate the positive test charge (1 Coulomb) already has a PD of + 5 Volts.)
Gravitational potential energy can be given by the equation PE = mgh where m is the mass, g is the gravitational constant 9.81 or 10 depending on rounding and h is the height
well weight is a force equiavlent to W= m*g
so comparing that to the potential energy equation, divide the potential energy by the height and you will get weight in Newtons
