Electricity review
21 Electrostatic Charges and Forces
Coulomb’s Law
Superposition of Forces
21 Electric Fields and Dipoles
Electric field, point charge
Uniform electric field
Charges in motion
Electric fields for certain shapes
Electric field lines
Dipoles, torque, potential energy
22,23 Electric Flux and Potential
Gauss’ Law
Flux
Potential energy of point charges
Electric potential
Electron Volt
Equipotential Surfaces
EF 152 Fall, 2009 Lecture 4-8
Electrostatic forces
24 Capacitance
Capacitors
Capacitors in a vacuum
Capacitors in series and parallel
Energy stored in a capacitor
Dielectrics
25 Current, Resistance, EMF
Current
Resistivity, conductance
Resistance
Electromotive force
Energy and power
Potential changes in a circuit
26 DC Circuits
Resistors in series and parallel
Kirchhoff’s rules
RC circuits
Applications
1
Electrostatic forces
EF 152 Fall, 2009 Lecture 4-8
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Electric potential
Find q
EF 152 Fall, 2009 Lecture 4-8
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Capacitance
EF 152 Fall, 2009 Lecture 4-8
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Capacitor dielectric
Calculate the voltage across each capacitor.
If C2=6.0 µF calculate the charge on the other capacitors.
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Resistance and power
Voltage, Power, Current, Resistance
The internal resistance of the power supply is 1700 Ω.
What is the current through the body and the power
dissipated in her body?
EF 152 Fall, 2009 Lecture 4-8
What is the resistance of a 150 W bulb?
How much current does the 150 W bulb draw?
7
Equivalent Resistance, Power
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Circuit
What is the maximum power the circuit can dissipate?
What are the unknown currents and voltages?
EF 152 Fall, 2009 Lecture 4-8
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RC circuit
A 700 Ω resistor is in series with a 7 µF capacitor. What capacitance must be
placed in parallel with the original capacitor to change the time constant to three
times its original value?
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EF 152 Fall, 2009 Lecture 4-8
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