Researched
Electromagnetism
Faraday (1831) and Maxwell (1865) unite electricity, magnetism and light in four equations; radio waves follow in 1887.
Open in the interactive tree →Faraday found that moving magnets induce current, the principle of generators and transformers. Maxwell condensed all known effects into four equations and predicted electromagnetic waves traveling at the speed of light, so light is one of them. Hertz produced radio waves in 1887. This theory underlies power grids, radio and electronics, and its conflict with Newton's mechanics led to relativity.
Prerequisites
- Calculus (Analysis)1684
- Newtonian Mechanics1687
- Partial Differential Equations1747Maxwell's equations are partial differential equations for electric and magnetic fields
- Electric Charge & Coulomb1785Oersted, Faraday and Maxwell extended the quantified electric force of Coulomb
- Voltaic Pile (First Battery)1800Oersted and Faraday needed a steady current from a battery
- Wave Optics (Young, Fresnel)1801Maxwell identified light as an electromagnetic wave after wave optics had shown it is a wave
Unlocks
- Dynamo & Electric Motor1831-1866
- Electric Telegraph1844
- Weather maps and services1854
- Rechargeable Battery1859
- Telephone1876Bell's telephone worked by electromagnetic induction
- Electrification1882
- Michelson-Morley Experiment1887
- Radio (Wireless Telegraphy)1895
- X-rays1895
- Discovery of the Electron1897
- Planck's Quantum of Action1900
- Electrocardiogram1903
- Theory of Relativity1905
- Vacuum Tube (Triode)1906
- Superconductivity1911
- Echo Sounding & Sonar1913
- EEG1924
- Quantum Mechanics1925
- Particle Accelerators1932
- Nuclear Physics1938
- First satellite (Sputnik)1957
- Laser1960
- Tokamak & Stellarator1968
- Magnetic brain stimulation1985
- Yang-Mills Mass Gapopen