Unit 3 · 6 lessons
Gravitational, Electric, and Magnetic Fields
Forces that act across empty space: gravity and orbits, electric forces, fields and potential, and the magnetic force on moving charges and currents.
- 63 practice questions
- 51 flashcards
Lessons
- 1Universal Gravitation and OrbitsThe law that pulls an apple down and holds the Moon in orbit, what gravitational field strength really measures, and how to work out the speed and period of any satellite.10 questions
- 2Gravitational Potential Energy, Escape Speed and Kepler's LawsWhy gravitational potential energy far from Earth is written as a negative number, how much energy it takes to change orbits or leave a planet for good, and how Kepler's three laws describe every orbit in the solar system.11 questions
- 3Electric Forces and FieldsCoulomb's law for the force between charges, how to add several electric forces as vectors, and the electric field that a charge sets up around itself.10 questions
- 4Electric Potential Energy and PotentialThe energy stored when charges are arranged, the potential that measures energy per coulomb, uniform fields between plates, the electron-volt, and how Millikan showed that charge comes in fixed units.11 questions
- 5Magnetic Fields and ForcesThe magnetic fields made by currents, the right-hand rules for their directions, the force on moving charges and on wires, circular paths, and the machines that use them.10 questions
- 6Charged Particles in Uniform Fields: Deflection and e/mHow an electron gun speeds charges up, why a charge crossing between parallel plates follows a parabola just like a thrown ball, and how J. J. Thomson combined electric and magnetic fields to measure the charge-to-mass ratio of the electron.11 questions