Download CH18 Electric Energy READ NOTES Serway

PHYSICS
Name __________________________________________ Date _____________
Energy: Conservation and Transfer
Phy.
3.1
Explain
charges and
electrostatic
systems.
Phy.3.1.1 Explain qualitatively the fundamental properties of the interactions of charged objects.
Phy.3.1.2 Explain the geometries and magnitudes of electric fields.
Phy.3.1.3 Explain how Coulomb’s law relates to the electrostatic interactions among charged
objects.
Phy.3.1.4 Explain the mechanisms for producing electrostatic charges, including charging by
friction, conduction, and induction.
Phy.3.1.5 Explain how differences in electrostatic potentials relate to the potential energy of
charged objects.
Text Reference: Physics (Serway) Chapter 18 Electrical
Energy & Capacitance
Section 18-1 Electric potential energy
ELECTRIC ENERGY AND ELECTRIC FORCE
 Electrical potential energy is energy associated with a __________________ object due to its
_________________ relative to a source of electric ______________________.

Electrical potential energy is a form of _______________________ energy.
o Any time a charge moves because of an electric force, whether from a uniform electric field or
from another group of charges, _______________ is done on that charge. See Figure 18-1.

Electric potential energy can be associated with a charge in a ______________________ field.
o Draw (or trace) Figure 18-2. How does a negative charge move with respect to electric field
lines?
o Write the electric potential energy in a uniform electric field equation & ID the symbols:
o Write the electrical potential energy for a pair of charges equation & ID the symbols & units:
Section 18-2 Potential difference
CHANGING ELECTRIC POTENTIAL
 Electrical __________________ is electrical _________________ _________________ divided by
___________________________.
o Write the electric potential equation & ID the symbols & units:
o The electric __________________ at a given point in an electric field is __________________
of the charge at that point.

Potential difference is a change in electric ________________________.
o Only __________________ in electric potential (______________________
___________________) from one position to another are useful in calculations.
o Write the potential difference equation & ID the symbols & units:
o Write the potential difference in a uniform electric field equation & ID the symbols & units:

Write the potential difference between a point at infinity and a point near a point charge equation:

A battery does ______________________ to move charges.
Section 18-3 Capacitance
CAPACITORS AND CHARGE STORAGE
 A __________________ is a device that is used to _________________ electrical potential energy.
 Capacitors will charge if a _____________________ ____________________ is applied. Once
charged, a capacitor can discharge if its plates are connected by a __________________ __________.
 Capacitance is the ratio of ______________________ to _____________________.
o Write the capacitance equation & ID the symbols & units:

Capacitance depends on the ________________ and ___________________ of the capacitor.
o Write the capacitance for a parallel-plate capacitor in a vacuum equation::

The material __________________ the plates of a capacitor can change its ____________________.
o The material in the space between the plates of a capacitor is called the ___________________.
Discharging capacitors ____________________ release their ___________________.
o Figure 18-8 shows a parallel-plate capacitor is often used in ________________________.

ENERGY AND CAPACITORS
 A charged capacitor stores electrical potential energy because it requires _________________ to move
charge through a circuit to the _____________________ plates of the capacitor.
 Write the electrical potential energy stored in a charged capacitor equation:
o Write the two alternate forms of this equation: