Theme D · Fields · Classes 34 to 36 · fields, potential and orbits
D Fields
Where gravitational, electric and magnetic fields come from; field strength; Newton’s law of gravitation and Coulomb’s law; magnetic field strength and currents; potential energy and potential; and circular orbits with escape speed.
Lessons
- D · 1What is a field?Where gravitational, electric and magnetic fields come from, and how we measure how strong they are. · D.1 / D.2 · Gravitational, electric and magnetic fieldsSL+HLEasier18 minFree
- D · 2Newton’s law of gravitation and Coulomb’s lawTwo force laws with the same shape: both fall off as 1 / r². Then the field of a point source. · D.1 / D.2 · Gravitational and electric force lawsSL+HLMedium22 minFree
- D · 3Magnetic field strength and currentsDefine B from the force on a moving charge, then on a wire, then between two wires. · D.2 · Magnetic fields, force between parallel currentsSL+HLMedium20 minFree
- D · 4Potential energy and potentialWork done is stored energy. Divide by the mass or charge and you get potential. · D.1 / D.2 · Gravitational and electric potentialSL+HLHarder24 minFree
- D · 5Orbits and escape speedGravity as the centripetal force: orbital speed, period, the energy of a satellite, and how fast to leave for good. · D.1 · Orbital motion, escape speedHLHarder28 minFree