 Current in DC Circuits
 Circuit Conventions
 Equivalent Resistance
 Kirchoff's Circuit Rules
 Measuring Voltage and Current
 Electromotive Force
 More on Solving Circuits
 Current and Current Density
 Ohm's Law, Resistance, and Resitivity
 Typical Values of Resistivity
 Resistance of a Cable
 Drift Velocity in Sea Water
Current in DC Circuits
Definition of current and current density; microscopic and macroscopic Ohm's Law.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
Circuit Conventions
Circuit element symbols; sign conventions; drawing resistors and capacitors.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
Equivalent Resistance
Rules governing resistors in series and parallel; how to calculate equivalent resistance in each.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
Kirchoff's Circuit Rules
Illustration of Kirchoff's Circuit Rules and method for solving a circuit; includes discussion of internal resistance in batteries.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
Measuring Voltage and Current
How to measure voltage, current, and resistance in a circuit.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
Electromotive Force
Definition from Efield; car batteries; direction of current flow.

8.022 Electricity and Magnetism, Fall 2004
Prof. Gabriella Sciolla
Course Material Related to This Topic:
More on Solving Circuits
Using Kirchhoff's rules to solve complex circuits; internal resistance and power dissipation.

8.022 Electricity and Magnetism, Fall 2004
Prof. Gabriella Sciolla
Course Material Related to This Topic:
Current and Current Density
Definition of macroscopic current and microscopic current density.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Read chapter 6, pages 2–4 of online textbook
Ohm's Law, Resistance, and Resitivity
Derivation of macroscopic Ohm's Law (V = IR) from microscopic; introduction of resistance, resistivity and conductivity, including temperature effect on resistivity.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Read chapter 6, pages 4–7 of online textbook
Typical Values of Resistivity
A table of values for resistivity and conductivity of several materials.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Read chapter 6, page 7 of online textbook
Resistance of a Cable
Given the dimensions and resistivity of a wire, determine its resistance. Solution is included after problem.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on pages 9–10
Drift Velocity in Sea Water
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.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on pages 11–2
Resistance of a Hollow Cylinder
Determine the resistance of a hollow cylinder between the ends and between the inside and outside. Solution is included after problem.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on pages 13–4
Conceptual Questions on Resistance and Power
Discuss the dependence of resistance on dimensions and temperature, and the dependence of power dissipation on resistance.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on page 14
Current of a Whirling Charge
A conceptual question about current density of a charged sphere spun in a circle.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on page 14
Ohm's Law for a Radiant Heater
Given the power and operating voltage of a radiant heater, find the current, resistance and output of the heater.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on pages 14–5
Drift Speed of Electrons in Copper Wire
How long does it take for an individual electron to travel from a car battery to the starter motor?

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on pages 15–6
Current Sheets
Describes the concept of a current sheet and explores the calculation of current density per unit length using a Van de Graaff belt example.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on page 16
Resistance of a Drawn Out Wire
How does the resistance of a wire change if it is drawn out so that its length is increased?

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on pages 16–7
Ohm's Law for a Lightbulb
Given the power and operating voltage of a lightbulb, find the current, resistance and electricity consumption of the bulb.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on page 17
Resistivity and Resistance
Identify how the resistance of a conductor depends on its length and area.

8.02 Physics II: Electricity and Magnetism, Spring 2007
Prof. John Belcher, Dr. Peter Dourmashkin, Prof. Robert Redwine, Prof. Bruce Knuteson, Prof. Gunther Roland, Prof. Bolek Wyslouch, Dr. Brian Wecht, Prof. Eric Katsavounidis, Prof. Robert Simcoe, Prof. Joseph Formaggio, Andy Neely, Matthew Strafuss, Prof. Eric Hudson, Dr. SenBen Liao
Course Material Related to This Topic:
 Complete practice problems on page 1
Bulbs in a Circuit
Determining relative brightness of light bulbs in a resistor circuit.

8.02X Physics II: Electricity and Magnetism with an Experimental Focus, Spring 2005
Dr. Peter Dourmashkin, Prof. Gunther Roland
Course Material Related to This Topic:
 Complete exam problem 1
 Check solution to exam problem 1