Physics Discoveries. 1600-1900

  • Willebrord Snell's Law of Refraction

    Willebrord Snell's Law of Refraction
    Snell's Law is used to describe the relationship between the angles of incidence and refraction, when referring to light or other waves passing through a boundary between two different media, such as water, glass and air.
  • Newton's inverse-square gravitational force law

    Newton's inverse-square gravitational force law
    Newton's law of universal gravitation states that two bodies with mass attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.
  • Ole Romer's Speed of light

    Ole Romer's Speed of light
    Romer determined that light has a finite speed and is not instantaneous. He found a value 26% lower than the true value by use of the orbital machanics of Jupiter's moons. Although he was wrong, his findings were the first intelligant assumption of the Speed of Light.
  • Christian Huygens' Principle of Wavefront Sources

    Christian Huygens' Principle of Wavefront Sources
    Huygens proposed that every point along a wave becomes a source of a new spherical wave. He assumed that the secondary waves travelled only in the forward direction and derived the laws of reflection and refraction using this principle.
  • Isaac Newton publishes his "Principia Mathematica"

    Isaac Newton publishes his "Principia Mathematica"
    This book was widely regarded as one of the most important works in both the science of physics and in applied mathematics during the Scientific revolution, the work underlies much of the technological and scientific advances from the Industrial Revolution.
  • Benjamin Franklin - "Lightning is Electricity "

    Benjamin Franklin - "Lightning is Electricity "
    Franklin proposed an experiment with conductive rods to attract lightning to a capacitor. He attached a key to the wet string of a kite and found that the key was negativly charged by lightning.
  • William Herschel discovers Uranus

    William Herschel discovers Uranus
    While in the garden of his house, Herschel reported it as a comet using a telescope of his own design. After reporting many astronomers took out to find out what it was. later a Russian scientist calculated the orbit and confiremed it was infact a planet.
  • Henry Cavendish' Mass of the Earth

    Henry Cavendish' Mass of the Earth
    This was the first experiment to measure the force of gravity between masses and the first to yield accurate values for the gravitational constant. However the value was first published as "The Mess of the Earth".
  • Alessandro Volta's Electric Battery

    Alessandro Volta's Electric Battery
    The battery made by Volta is credited as the first electrochemic cell. It consists of two electrodes: one made of zinc, the other of copper. The electrolyte is either sulfuric acid mixed with water or a form of saltwater brine.
  • Hans Oersted's Electricity and Magnetism

    Hans Oersted's Electricity and Magnetism
    When preforming a simple experement with currents and metal wires, Hans placed a compas near the wire and found that the compas was affected by the current. This was the first concrete evidence of the connection between electricity and magnetism
  • Michael Faraday's Electric Motor

    Michael Faraday's Electric Motor
    His motor was made with a wire in a container of mercury and a bar magnet in the center of the container. He sent electricity through the wire and created a magnetic field around it. This interacted with the field around the magnet and caused the wire to rotate around the magnet.
  • Georg Ohm - Ohm's Law

    Georg Ohm - Ohm's Law
    Using equipment of his own creation, Ohm found that there is a direct proportionality between the voltage applied across a conductor and the resultant electric current. This relationship is known as Ohm's law.
  • Lord Kelvin's absolute zero

     Lord Kelvin's absolute zero
    It is commonly thought of as the lowest temperature possible and is taken as −273.15°C (459°F). Kelvin calculated this using the ideal gas law; this is a gas that isn't real but represents the properties of many gases in a machanical context.
  • Foucault's Speed of Light

    Foucault's Speed of Light
    Foucault measured the speed of light in water and found that it is slower than in air.
  • Heinrich Hertz's Photoelectric Effect

    Heinrich Hertz's Photoelectric Effect
    Hertz observed the photoelectric effect and the production and reception of electromagnetic waves. His experement consisted of a coil with a spark gap, where a spark would be seen upon detection of electromagnetic waves.
  • Joseph Thomson Discovers the Electron

    Joseph Thomson Discovers the Electron
    At the Cavendish Laboratory at Cambridge University, Thomson was experimenting with currents of electricity inside empty glass tubes.He called these particles "corpuscles," and suggested that they might make up all of the matter in atoms.
  • Max Planck - Planck's constant

    Max Planck -  Planck's constant
    Planck was investigating the problem of black-body radiation when he found that a hot object is in equilibrium with light, the amount of light it absorbs is equal to the amount of light it emits meaning it absorbs all the light that hits it.
    He realised he accidently found a value that must remain the same. 6.62606957 × 10-34 m2 kg / s
  • Albert Einstein's Theory of Special Relativity

    Albert Einstein's Theory of Special Relativity
    In his initial presentation of special relativity in 1905 he expressed two main theories. The Principle of Relativity and The Principle of Invariant Light Speed.
  • Edwin Hubble's Expansion of the Universe

    Edwin Hubble's  Expansion of the Universe
    He was aware that a decade earlier astronomer Vesto Slipher had measured the Doppler shift of several galaxies, finding that most were moving away at very high speeds. Hubble carefully measured the distance and Doppler shift of as many galaxies as possible and that would lead to the realization that the universe was expanding.
  • James Chadwick Discovers the Neutron

    James Chadwick Discovers the Neutron
    Chadwick dropped all his other responsibilities to concentrate on the neutron, frequently working late at night. He devised a simple apparatus after only about two weeks of experimentation Chadwick sent a letter to Nature titled Possible Existence of a Neutron.
  • Charles Townes Invents the Maser

    Charles Townes Invents the Maser
    Townes invented the maser (microwave amplification by stimulated emission of radiation), using ammonia gas and microwave radiation - the maser was invented before the laser. The technology is very close but does not use a visible light.