Micro-model of Charge, Q-transfer, Conductors vs. Insulators

Electric charges are all around us. They are responsible for many of the phenomena we see, including the true nature of the normal force. Some charges can move and some can reorient to create interesting effects.

• Lecture 1 | Micro-model of Charge, Q-transfer, Conductors vs. Insulators

Electric Forces & Coulomb's Law

Atoms are comprised of charges. The positively charged nucleus is attracted to the negatively charged electrons. Molecules, which are comprised of atoms, also bind together due to this charge related force of attraction. Solids and liquids, comprised of molecules, also bind together due to the electric force of charges. All forces we experience, except gravity, are due to the electric force.

• Lecture 2 | Electric Forces & Coulomb's Law

Field Model, Charges in an Electric Field

Spiders ride electric fields to fly hundreds of miles.

• Lecture 1 | Field Model, Charges in an Electric Field

Electric Field from Point Charges

All charged objects produce a thing we call their electric field. It is not observable in the conventional sense and might be thought of as a clever way to keep track of how charged objects interact. The field from one electron can influence another electron and the result is they feel a repelling force.

• Lecture 2 | Electric Field from Point Charges

Electric Fields Patterns

Check out the field patterns displayed in this video.

• Lecture 3 | Electric Fields Patterns

Electric Potential & Electric Potential Energy

Imagine a universe that only consists of two protons, initiall at rest and very close to each other. We know what will happen, they will repel each other and accelerate away in opposite directions. In the initial state they had zero kinetic energy but that doesn't last. Where did that energy come from?

• Lecture 1 | Electric Potential & Electric Potential Energy

EP Field Patterns & Motion of Charges

Check out the equipotential surfaces of a bunch of charges dancing around each other.

• Lecture 2 | EP Field Patterns & Motion of Charges

Connecting Electric Potential & Electric Field

It is easy to measure the electric potential using a volt meter. If you can map out the voltage in some region of space, you can determine the electric field from that voltage map. It is in this way that once you know the electric potential, you know everything.

• Lecture 3 | Connecting Electric Potential & Electric Field

Micro-model of Charge Flow, Resistance, Ohm's Law, Power

Check out Crash Course Physics's introduction to electrical current.

• Lecture 1 | Micro-model of Charge Flow, Resistance, Ohm's Law, Power

Kirchoff's Laws

Circuits exist in lots of everday items, from cell phones, to computers, to cars, to toasters. Anything that requires electricity to operate, has some form of circuit. Here we study circuits that have constant voltage sources, like a battery, and resistive elements, like a lightbulb.

• Lecture 2 | Kirchoff's Laws

Equivalent Circuits

Check out this short animation of simplifying a circuit.

• Lecture 3 | Equivalent Circuits

Magnetic Fields, Magnetism

Slow Motion Magnetic Fields!

• Lecture 1 | Magnetic Fields, Magnetism

Magnetic Force, UCM

A cathode ray tube creates a stream of electrons you can see. These electrons are deflected in their motion when they travel through a magnetic field.

• Lecture 2 | Magnetic Force, UCM

Motional EMF, Induced Currents

Observing motional EMF is as easy as plucking a metal guitar string next to a magnet. Okay, you also need an oscilloscope and the lessons learned in this class :)

• Lecture 1 | Motional EMF, Induced Currents

Faraday & Lenz's Law

World's simplest electric train (or so they claim).

• Lecture 2 | Faraday & Lenz's Law