Answer to Question #307487 in Electricity and Magnetism for Shane

Question

1. The potential energy of a certain system of two charges increases as the charges are moved farther apart. What does

this tell us about the sign of the charges? Why?

2. Show that volt per meter is the same as newton per coulomb.

3. A student said "electric potential is always proportional to potential energy; why bother with the concept of potential at

all? How would you respond?

Answer 1

Answer

1.according to concepts,

The potential energy is inversely proportional to square of distance between the charges.It also depends whether both charges are of same or opposite sign, if both are of same sign then potential energy will decrease and if opposite charges then it will increase.

2.Electric field is given by

$E=\frac{F}{q}=\frac{V}{d}$

This equation relate the both

volt per meter is the same as newton per coulomb.

3.this is because Electric Potential Energy requires a test charge to calculate, Electric Potential is present without a test charge.