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Definition, with example of calculating the drift velocity current for a copper wire.
Statement of Ohm's Law with definitions of conductivity, resistance, and resistivity.
Comparison of the properties of good conductors and good insulators.
Explanation that temperature can cause Ohm's Law to break down. Includes a demonstration of Ohm's Law holding for one resistor and not for another.
Ohm's Law failing to hold for a light bulb with a resistance that varies with temperature.
Definition and comparison of values for resistance, current, and voltage.
Using a candle to increase the conductivity of air near an electroscope.
Using salt to increase the conductivity of water and light a bulb.
Calculation of resistance between body and Earth through a pair of shoes, including a demonstration that this resistance is not high enough to keep charge from flowing.
Definition and explanation of how a battery works, with examples.
Symbol for a battery in a circuit diagram, definition of electromotive force and internal resistance.
Connecting two batteries in series to demonstrate that the electromotive force doubles.
Derivation of the equation for power P=IV, including definition of Watts as unit of power.
Finding the power consumed by a resistor, with examples including light bulbs, heaters, and the human body.
Finding the power supplied by a battery, with a demonstration of a 9 V battery being shorted out.
Showing the large current and power supplied by a car battery when it is shorted out.
Finding currents and power in a circuit of batteries and resistors.
Discussion of the advantages of transporting electric energy at high voltages to minimize power loss. Calculation of the maximum voltage possible without causing corona discharge, including a slide of corona discharge on a power line during a storm.
Definition of current and current density; microscopic and macroscopic Ohm's Law.
Circuit element symbols; sign conventions; drawing resistors and capacitors.
Rules governing resistors in series and parallel; how to calculate equivalent resistance in each.
Illustration of Kirchoff's Circuit Rules and method for solving a circuit; includes discussion of internal resistance in batteries.
How to measure voltage, current, and resistance in a circuit.
Definition from E-field; car batteries; direction of current flow.
Using Kirchhoff's rules to solve complex circuits; internal resistance and power dissipation.
Definition of macroscopic current and microscopic current density.
Derivation of macroscopic Ohm's Law (V = IR) from microscopic; introduction of resistance, resistivity and conductivity, including temperature effect on resistivity.
A table of values for resistivity and conductivity of several materials.
Given the dimensions and resistivity of a wire, determine its resistance. Solution is included after problem.
Find the average drift velocity for ions in a tube of sea water when a voltage is applied across its length. Solution is included after problem.
Determine the resistance of a hollow cylinder between the ends and between the inside and outside. Solution is included after problem.
Discuss the dependence of resistance on dimensions and temperature, and the dependence of power dissipation on resistance.
A conceptual question about current density of a charged sphere spun in a circle.
Given the power and operating voltage of a radiant heater, find the current, resistance and output of the heater.
How long does it take for an individual electron to travel from a car battery to the starter motor?
Describes the concept of a current sheet and explores the calculation of current density per unit length using a Van de Graaff belt example.
How does the resistance of a wire change if it is drawn out so that its length is increased?
Given the power and operating voltage of a lightbulb, find the current, resistance and electricity consumption of the bulb.
Identify how the resistance of a conductor depends on its length and area.
5-part power problem; finding resistance, power, voltage conditions, and Lorentz force in power lines.
5-part problem; determining which bulbs in a circuit are lit when various switches are closed and which are brightest.
Determining relative brightness of light bulbs in a resistor circuit.