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Electric Potential. Electric forces are conservative. Work done by an electric force is W=- q o Ed D U=-W. Figure 20-1 Change in Electric Potential Energy. Electric Potential. Definition of Electric Potential V. Electric Potential.
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Electric Potential Electric forces are conservative. Work done by an electric force is W=-qoEd DU=-W
Electric Potential Definition of Electric Potential V
Electric Potential When working with electric potential we measure only changes in electric potential. The zero point can be set arbitrarily.
Electric Potential Electric field and the rate of change of electric potential.
Electric Potential Electric potential of point charges.
Electric fields around conductors Excess electric charges move to the surface of a conductor because that is where they are least affected by the internal charges of the material.
Electric fields around conductors When electric charges are at rest, the electric field within a conductor is zero. This works even if the conductor has an internal cavity.
Electric fields around conductors Electric field lines enter conductor surfaces at right angles.
Electric fields around conductors Electric field lines are more intense near a sharp point.
Capacitors A capacitor is a device that has the ability “capacity” to store electric charge and energy.
Capacitors A dielectric material is an insulator that increases the capacitance of a capacitor when placed between the plates. Each material has a dielectric constant k not to be confused with k.(p 665)
Figure 20-15The Effect of a Dielectric on the Electric Field of a Capacitor