History of Light by yeah https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0 en-us 2023-03-09 17:58:04 UTC 2023-03-31 17:27:38 UTC hello@padlet.com https://padlet.net/icons/png/1f92a.png Albert Einstein (1879-1955) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510718102 German theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Best known for the theory of relativity and his work with quantum physics.]]> 2023-03-09 18:12:23 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510718102 The First Moment of Light https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510721352 Once the universe was finally cool enough for atoms to attract free electrons, they were transformed into neutral atoms, therefore producing the first ever light. ]]> 2023-03-09 18:14:47 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510721352 Christiaan Huygens (1629-1695) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510736117 Huygens was Dutch mathematician, physicist, engineer, astronomer, and inventor. He worked on the wave theory of light, pendulum clocks, and centrifugal force.]]> 2023-03-09 18:26:07 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510736117 Michael Faraday (1791-1867) wyatt223251 https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510746069 Michael Faraday was born in England and died in Surrey. Throughout his life, he was very ambitious and wanted to expand his knowledge of chemistry and, eventually, electromagnetism.

Throughout his life, he made many advancements in technology relating to electromagnetism, light, and other valuable concepts. ]]> 2023-03-09 18:33:29 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510746069 Euclid (c.300BCE-200BCE) APPhysII5thHour https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510746732 Euclid was a renowned Greco-Roman mathematician and geometrician who had several valuable theories about light. These shaped our perception of light in the present day. 

His theories included:

Light rays are straight lines

We only see things that light touches

Light rays with a large range of angles make an object appear big, and small with many similar angles.

Euclid also wrote several books, most noticably, Optiks, about the geometry of light and seeing.
]]> 2023-03-09 18:33:59 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510746732 Max Planck (1858-1947) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510749990 Max Planck was a German theoretical physicist known as the originator of quantum theory and Planck’s constant. Scientists tried calculating the radiation given off using current physical laws, yielding infinite radiation. Using his theory of “quanta” Planck determined that overall energy is equal to the frequency of the radiation times a constant now known as Planck’s constant. He created quantum theory which states that matter and energy are based on “quanta.”  His quantification of light led us to believe that light is made up of mass-less particles called photons and not a continuous wave as previously thought.  He won a noble prize for his theory in 1918. 
  
]]> 2023-03-09 18:36:23 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510749990 Aristotle (384 B.C. - 322 B.C.) timothy223716 https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510751184 Aristotle conducted experiments with light and vision, and his work on these topics had a significant influence on subsequent philosophers and scientists. He explored the properties of light, including its reflection, refraction, and transmission, and developed a theory of vision that posited that the eye functions by receiving and processing sensory information from the surrounding environment.  Today, his work on light and vision is still studied and debated. Some of his original ideas such as light being a particle has been disproven. ]]> 2023-03-09 18:37:07 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510751184 Heinrich Hertz (1857-1894) oldanid1 https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510758098 Heinrich Hertz, a German-born physicist, was most known for his discovery of electromagnetic radiation by producing radio waves. Using this discovery, he was able to prove Maxwell's theory of electromagnetism.]]> 2023-03-09 18:42:25 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510758098 Plato (428 B.C. - 347 B. C.) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510759710 During the Classical era in ancient Greece, the philosopher Plato was born in Athens. Plato established the Academy, a school for philosophy in Athens, where he first taught the ideas that would eventually come to be known as Platonism.

Plato's theory about light was:

Plato is credited with being the first to articulate the emission theory of vision. This theory, which persisted until the second millennium AD, held that the eye projected a beam of light like a flashlight, illuminating objects in front of it. When something blocked the "eye ray" the result was darkness. ]]> 2023-03-09 18:43:40 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510759710 James Clerk Maxwell (1831-1879) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510762419 James Clerk Maxwell was a Scottish physicist who was best known for his formulation of the electromagnetic theory. He concluded that the speed of transverse waves were equal to the speed of light. ]]> 2023-03-09 18:45:52 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510762419 Einstein's Photoelectric Effect (1905) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510763798 2023-03-09 18:46:54 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510763798 Socrates (470 B.C. - 399 B.C.) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510765213 Socrates was a Greek philosopher who is credited as one of the most influential and well-known philosophers of his time. He did not keep a record of many of his teachings and beliefs as they were recorded by the students he taught. A plethora of concepts relating to morals and ethics can be attributed to Socrates, but his most influential addition to the scientific and philosophical world is the implementation of the Socratic Method, which has become a major foundation of scientific research and philosophical discussion throughout human contemplation.  

The Socratic Method is a process that encourages critical thinking through discussion, argument, and dialogue between peers in order to discern the truth of a subject. Participants would make assertions about subjects, investigate properties that surround said subjects, and ask questions to create new connections between ideas and come to a mutual agreement on the cause, effect, or reason for something to happen. Although an agreement was not always guaranteed, critical thinking is stimulated, and it allows for new hypotheses to be formed. This method of thinking paved the way for future thinkers, like his students Plato, and later on, Aristotle, to continuously strive for a better understanding of the world we live in.  
]]> 2023-03-09 18:47:59 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510765213 Ibn al-Haytham (c.965 - c.1040) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510767486 Ibn al-Haytham was an Arab mathematician, physicist, astronomer, and an intellect in several other fields of study. He is referred to as “the Father of Modern Optics” as he made several major contributions to develop the modern understanding of optics through works such as his “Book of Optics,” which included 7 volumes worth of his ideas and experiments that proved his theories of how light was perceived by humans. His procedure of explaining his theories through experimentation were some of the first of it’s kind, and this methodology earned him the title of the world’s “first true scientist.” Haytham also introduced his scientific method through his book of optics, which consists of observation, hypothesis, experimentation, and independent verification. This is very similar to the modern-day approach scientists take.  

Some of the important concepts that Haytham experimented with related to lenses, mirrors, and reflection/refraction, which were all featured in his Book of Optics. Here are some of his discoveries and important experiments. 

- Theory of Optics
- Law of Refraction
- Alhazen's Problem
- The Camera Obscura and Pinhole Camera
]]> 2023-03-09 18:49:39 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510767486 Thomas Young (1773- 1829) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510769424 Thomas Young Was a British polymath who made notable contributions to the fields of vision, light, solid mechanics, energy, physiology, language, musical harmony, and Egyptology. ]]> 2023-03-09 18:51:17 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2510769424 Albert A. Michelson (1852-1931) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512176838 Born on December 19, 1852, Albert Abraham Michelson was born in Strelno, Prussia and soon then moved to Virginia City, Nevada, two years later. After receiving an appointment from President Grant, he attended and graduated from the U.S. Naval Academy and later became a professor of physics and chemistry there. After leaving the navy, he performed many experiments to measure the speed of light as well as discover if light travels through a medium. While experimenting, he discovered and used his interferometer, a way to produce light with extreme precision, which helped him discover the relationship between the motion of the earth and its velocity. This also helped him discover that light doesn’t travel through any medium with help from Edward Morley.

]]> 2023-03-10 18:03:58 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512176838 Isaac Newton (1642-1727)- made calc bc bad https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512179232 Isaac Newton is best know for his theory about the law of gravity, but his “Principia Mathematica” (1686) with its three laws of motion greatly influenced the Enlightenment in Europe. Sir Isaac Newton began developing his theories on light, calculus and celestial mechanics while on break from Cambridge University.

Newtons theory: He had a major influence on the world on science, this theory was a popular belief for a long time. It was abandoned in the 19th century for the wave theory. Light consisted of minute corpuscles in rapid motion, which emanated from their source and were scattered in the atmosphere.


]]> 2023-03-10 18:06:06 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512179232 Edward W. Morley (1838 - 1923) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512184110 The Michelson-Morley Experiment and the exact and accurate determination of the atomic weight of oxygen are two achievements of American physicist Edward Williams Morley.]]> 2023-03-10 18:10:23 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512184110 Genesis 1:3 timothy223716 https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512184326 And God said, “Let there be light,” and there was light.]]> 2023-03-10 18:10:36 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512184326 Augustin-Jean Fresnel (1788-1827) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512190493 Augustin-Jean Fresnel was a French civil engineer and physicist. His research in optics led to a nearly unanimous acceptance of the wave theory of light, excluding any remnant of Newton's corpuscular theory, from the late 1830s until the end of the 19th century. He proved that light is a transversal wave.

]]> 2023-03-10 18:16:19 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512190493 Fresnel Lens (1822) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512199388 The Fresnel lens was used in lighthouse optics to concentrate the light into narrow and bright beam. This technology was and is still used in some cars, solar cookers, and theaters. ]]> 2023-03-10 18:25:36 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512199388 1703- Newt publishes findings on light https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512202499 This experiment was conducted to disprove the wave theory and it explained the phenomenon of reflection, refraction, and rectilinear propagation of light. He let one beam of sunlight (which is white light) pass through a glass prism. He observed that the light scattered into several colors resembling a rainbow. He named this multicolored band of light a color spectrum. He split these colors into the seven categories (ROYGBIV). Newton then passed the beam of sunlight through a second prism that was held upside down so that the spectrum passing through the first prism was recomposed into white light. He observed that all objects appear to be the same color as the beam of colored light that illuminates them and that a beam of coloured light will stay the same colour no matter how many times it is reflected or refracted. This led him to conclude that color is a property of the light that reflects from objects and not a property of the objects themselves.

]]> 2023-03-10 18:28:35 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512202499 Froome's New Determination Experiment (1958) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512203786 2023-03-10 18:29:53 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512203786 Faraday Effect (1845) wyatt223251 https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512209159 In 1845, Faraday discovered that polarized light can be influenced by a magnetic field. He wanted to determine that forces in nature were all connected. ­In an experiment he observed that polarized light that travels straight through a parallel magnetic field would experience a rotation of the plane of polarization. This proved that the polarization plane of a light wave is rotated when a magnetic field is applied. This is now known as the Faraday effect. 

This effect is what has allowed technology in fiber-optics to be developed. It is through fiber-optics that much of our communication occurs and data can be sent across long distances very quickly. ]]> 2023-03-10 18:35:32 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512209159 1801- Double-slit Experiment https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512212659 This experiment was performed on by Thomas Young. The double-slit experiment was set up with two tiny slits/pinholes so that light can pass through it. Behind those slits was a screen that showed the result of the passage of light. The light that passed through the two pinholes mix and create a ripple-type effect. In some places the light from the two holes combines (constructive interference), whereas in others they cancel each other out (destructive interference), thus producing the pattern of bright and dark lines. Because of this Thomas Young concluded that light is less like a particle and more like a wave. He disproved Newton’s previous theory that everyone at the time thought was true. Newton’s particle theory of light fell into disuse. ]]> 2023-03-10 18:38:55 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512212659 Michelson-Morley Experiment (1887) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512216330 In order to track the velocity of Earth through the ether as it orbited the Sun, Michelson and American chemist Edward Morley conducted a precise set of optical observations in 1887. Earth offers a favorable vantage point for detecting any change in the relative speed of light owing to motion because its speed is around 29,000 meters per second, or roughly 0.01 percent of the speed of light. Throughout the course of the Earth's orbit, interference effects between two light beams traveling perpendicular to and parallel to its orbital motion were seen using a Michelson optical interferometer. A change in light speed along the two interferometer routes as tiny as 5,000 meters per second might be detected by the equipment (less than 2 parts in 100,000 of the speed of light). No differences were discovered. The measured speed of light appeared to be unaffected, even though Earth was moving through the ether.]]> 2023-03-10 18:42:04 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512216330 Fresnel Huygens Principle (1678) https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512225164 The Fresnel-Huygens Principle was first theorized in 1678 by Huygens, but later adopted by Fresnel. The principle states that all points of a wave of light in a transparent medium or vacuum may be a new source of wavelets that expands in every direction at a rate dependent on their velocities. ]]> 2023-03-10 18:51:24 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2512225164 The Michelson-Morley-Experiment https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2539164122 Performed in July of 1887 at Western Reserve University, the Michelson-Morley-Experiment asked the question of whether there is a medium that light travels through called ether. This theoretical ether would cause light to move in a separate direction while traveling towards the mirrors (almost like wind pushing it). For example, think of a person running a 100-meter race facing north. If the wind (ether) were moving from southwest to northeast, the runner (light) would be propelled in the northwest direction and theoretically run faster. To test this theory, they used Michelson’s interferometer that produces light with extreme precision and reflected the light onto two separate mirrors to see if their reflections would return at the same time. After several experiments they saw that the beams of light returned at the same time and discovered that there is no medium that light travels through. Years later, Einstein used the information Michelson and Morley found to discover his theory on light and relativity. 

]]> 2023-03-31 01:21:55 UTC https://padlet.com/APPhysII5thHour/t7sofpzoumrywid0/wish/2539164122