1. Road Map – Getting closer!! Electrostatics Circuits Non-moving Charges Moving Charges Electric Field Electric Potential

2. The Great Opposites of Our Time Gravity has only one direction… While Electric Charges/Electric fields have two directions…. Happy/Sad Hot/Cold Clemson/Universit y of SC

3. Electric Potential Electric charges both generate and react to the electric field, but they also warp the field three-dimensionally

4. Electric Potential Electric Potential – the ‘steepness’ or warping of the electric field due to the presence of an electric charge.

5. Measuring Electric Potential Two ways!! Method #1 If you know the value of the point charge… ….the electric potential can be measured based on distance V = Electric Potential k = 8.99 x 10 9 q = point charge (no absolute value) r = distance away SI Unit for Electric Potential: Volt (v)

6. Example 5 A.Calculate the electric potential from a point source (+4.65 x 10 -7 C) at a distance of 2.50 m away and 4.00 m away. B.How far away from a point source ( -4.65 x 10 -7 C) would you have to be to have an electric potential of -550 v?

7. Example 6 Two point charges (q 1 and q 2 ) are located in the same plane. The first charge (q 1 ) has a charge of -1.00  C and is located at point (0, 1.00). The second charge (q 2 ) has a charge of +1.00  C and is located at point (2.00, 0). A.What is the value of the electric potential at the origin from q 1 ? B.What is the value of the electric potential at the origin from q 2 ? C.What is the net electric potential at the origin?

8. Electric Potential Method #2 Electric Potential is measured as the electric potential energy (EPE) per unit charge…. q = electric charge EPE = Electric Potential Energy Measured in Joules V = Electric Potential

9. Electric Potential Energy Electric Potential Energy results when we move, push, or force charged particles against their will. + + We have to do work to move a charge against its will. Work done by me = Energy gained by particle SI Unit for Energy: Joules (J)