Transcript electrical charge

Electric Field
Cues
 Gaining Charge
 Analogy
 Electric Field
 What is the difference?
 Electrical Fields
 Electrical Potential
Gaining Charge
 How does a piece of matter become
charged?
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What does a neutral charged atom look like?
What does a positively charged atom look
like?
What does a negatively charged atom look
like?
Analogy
The electric field is the space
around an electrical charge
just like
a gravitational field is the space
around a mass.
Electric Field
 Space around a charge.
What is the difference?
Van de Graaff Generator
 Builds up static electric
charges.
Electric Field Lines
Electric Field Lines of two Positive
Charges
Electric Field Lines
 Lines that indicate the strength and
direction of the electric field.
 The more dense the lines, the stronger the
field.
 Electric field vectors are tangent to the
curve.
 Simulation
http://online.cctt.org/physicslab/content/applets/
pointcharges/elefi_z.htm
Video
 http://www.youtube.com/watch?v=vaDT4GwA
Z2I
Which field is stronger?
A
B
Question
 If a test charge is moved to a location three
times as far as its original location, how does
the electric field change?
Electrical Potential
 Remember that all energy can be kinetic and
potential.
 Electricity has potential:
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This energy comes from the charge particle
has due to its position in an electric field.
Because like charges repel, it takes energy to
push a charged particle closer to another
particle with a like charge. That energy is
stored as the electric potential energy. These
particles can move and want to/will when it is
free to move.
Electrical Potential
 To push a charged particle closer to another
particle with the same charge takes a certain
amount of energy.
 As the particles move closer and closer
together their potential increases.