Experimental basis for special relativity
... • If there was a medium for light wave propagation, then the speed of light must be measured relative to that medium • Thus the ether could provide an absolute reference frame for all measurements • The ether must have some strange properties – it must be solid-like to support high-frequency transve ...
... • If there was a medium for light wave propagation, then the speed of light must be measured relative to that medium • Thus the ether could provide an absolute reference frame for all measurements • The ether must have some strange properties – it must be solid-like to support high-frequency transve ...
Determination of Planck`s Constant
... where νo is the threshold frequency below which no photoemission occurs, and h is a constant. The value of h, Planck’s constant, (6.626 × 10–34 J·s = 4.136 × 10–15 eV·s), is always the same, whereas νo varies with the particular metal being illuminated. Also, within the limits of experimental accura ...
... where νo is the threshold frequency below which no photoemission occurs, and h is a constant. The value of h, Planck’s constant, (6.626 × 10–34 J·s = 4.136 × 10–15 eV·s), is always the same, whereas νo varies with the particular metal being illuminated. Also, within the limits of experimental accura ...
4.3 Wave characteristics
... Wave intensity For example, imagine a window with an area of 1m2. If one joule of light energy flows through that window every second we say the light intensity is 1 W.m-2. ...
... Wave intensity For example, imagine a window with an area of 1m2. If one joule of light energy flows through that window every second we say the light intensity is 1 W.m-2. ...
Perspectives of QM
... Now, it is believed that if the intensity of the source is reduced, the wave description is still valid and one should expect an interference pattern with small intensity. Now, it is possible to detect one photon. Then, if the intensity is reduced to such that there is only one photon in the instrum ...
... Now, it is believed that if the intensity of the source is reduced, the wave description is still valid and one should expect an interference pattern with small intensity. Now, it is possible to detect one photon. Then, if the intensity is reduced to such that there is only one photon in the instrum ...
Big Idea Waves 1 Pupil feedback sheet
... pupil, iris, lens, retina, optic nerve I can state the functions of the main parts of the human eye: cornea, pupil, iris, lens, retina, optic nerve I can list the colours of the spectrum in light in order I can give some examples of when light is absorbed or reflected I can describe what is meant by ...
... pupil, iris, lens, retina, optic nerve I can state the functions of the main parts of the human eye: cornea, pupil, iris, lens, retina, optic nerve I can list the colours of the spectrum in light in order I can give some examples of when light is absorbed or reflected I can describe what is meant by ...
Section 9.4: Light: Wave or Particle?
... diffraction were a result of collisions between light particles at the edges of the slit, and not a result of waves of light spreading out. By the time Newton wrote Opticks, his book on light, he explained diffraction as a kind of refraction. This is since understood to be incorrect. Newton’s greate ...
... diffraction were a result of collisions between light particles at the edges of the slit, and not a result of waves of light spreading out. By the time Newton wrote Opticks, his book on light, he explained diffraction as a kind of refraction. This is since understood to be incorrect. Newton’s greate ...
Chapter 24
... When charges vibrate, they act like tiny antennas. The electric field will oscillate in the direction of the vibration. Because vibration can occur in all directions, the resultant e-m wave is a superposition of the waves produced by the vibrating charges. This results in unpolarized light. If the ...
... When charges vibrate, they act like tiny antennas. The electric field will oscillate in the direction of the vibration. Because vibration can occur in all directions, the resultant e-m wave is a superposition of the waves produced by the vibrating charges. This results in unpolarized light. If the ...
Light Rays
... All points on a given wave front are taken as point sources for the production of spherical secondary waves, called wavelets, that propagate outward through a medium with speeds characteristic of waves in that medium. After some time interval has passed, the new position of the wave front is the sur ...
... All points on a given wave front are taken as point sources for the production of spherical secondary waves, called wavelets, that propagate outward through a medium with speeds characteristic of waves in that medium. After some time interval has passed, the new position of the wave front is the sur ...
Speed of Light Measurement Utilizing Octagonal
... speed of light. One should be able to obtain very precise results from simply lengthening the optical path length, the focal length of the lens, and increasing the rotational frequency. The main obstacle in these measurements will be to have a beam intense enough to view. Because our optical path le ...
... speed of light. One should be able to obtain very precise results from simply lengthening the optical path length, the focal length of the lens, and increasing the rotational frequency. The main obstacle in these measurements will be to have a beam intense enough to view. Because our optical path le ...
Light
Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum. The word usually refers to visible light, which is visible to the human eye and is responsible for the sense of sight. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), or 6993400000000000000♠400×10−9 m to 6993700000000000000♠700×10−9 m, between the infrared (with longer wavelengths) and the ultraviolet (with shorter wavelengths). This wavelength means a frequency range of roughly 430–750 terahertz (THz). Often, infrared and ultraviolet are also called light.The main source of light on Earth is the Sun. Sunlight provides the energy that green plants use to create sugars mostly in the form of starches, which release energy into the living things that digest them. This process of photosynthesis provides virtually all the energy used by living things. Historically, another important source of light for humans has been fire, from ancient campfires to modern kerosene lamps. With the development of electric lights and of power systems, electric lighting has all but replaced firelight. Some species of animals generate their own light, called bioluminescence. For example, fireflies use light to locate mates, and vampire squids use it to hide themselves from prey.Primary properties of visible light are intensity, propagation direction, frequency or wavelength spectrum, and polarisation, while its speed in a vacuum, 299,792,458 meters per second, is one of the fundamental constants of nature. Visible light, as with all types of electromagnetic radiation (EMR), is experimentally found to always move at this speed in vacuum.In physics, the term light sometimes refers to electromagnetic radiation of any wavelength, whether visible or not. In this sense, gamma rays, X-rays, microwaves and radio waves are also light. Like all types of light, visible light is emitted and absorbed in tiny ""packets"" called photons, and exhibits properties of both waves and particles. This property is referred to as the wave–particle duality. The study of light, known as optics, is an important research area in modern physics.