Category: Index
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Speed of Light
Introduction The speed of light, typically denoted by , is a fundamental constant of nature that represents the speed at which light travels in a vacuum. It is an important concept in many areas of physics, such as electromagnetism and relativity. Value and Units The speed of light in a vacuum is defined to be…
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Brillouin Scattering
Introduction Brillouin scattering is a phenomenon in physics involving the interaction of light with material waves within a medium. This interaction causes the light to be scattered and its frequency to shift, an effect known as the Brillouin shift. Basics of Light Scattering When light is incident on a medium, it can be absorbed, transmitted,…
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Ultrasonics
Introduction to Ultrasonics Ultrasonics refers to the study and application of mechanical waves with a frequency above the upper limit of human hearing, typically considered to be around 20 kHz. These waves can propagate through various media, including gases, liquids, and solids. Basics of Sound Waves Sound waves are longitudinal waves that travel through a…
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Shadows
Introduction In the study of light and shadows, two terms are of key importance: umbra and penumbra. The umbra is the darkest part of a shadow, while the penumbra is a lighter shadow that appears when some but not all of the light source is blocked. Physics of Light and Shadows When light encounters an…
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Weightlessness
Introduction Weightlessness is a condition experienced by a body when it is free-falling under the influence of a gravitational field, with no other forces (like the normal force) to counteract it. Despite the name, weightlessness doesn’t mean that an object’s weight becomes zero, but rather it refers to the feeling of having no weight because…
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Spherical Harmonics
Introduction Spherical harmonics are mathematical functions that play a significant role in various fields, including quantum mechanics, electrodynamics, and computer graphics. They arise when solving Laplace’s equation in spherical coordinates, leading to a separation of variables solution. Definition and Mathematical Formulation of Spherical Harmonics Spherical harmonics can be defined in terms of the associated Legendre…
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Yttrium Barium Copper Oxide (YBCO)
Introduction Yttrium Barium Copper Oxide (YBCO) is a type of cuprate high-temperature superconductor characterized by the formula (often abbreviated to Y-123). These materials exhibit superconductivity—a phenomenon characterized by the complete absence of electrical resistance—at temperatures significantly higher than traditional superconductors, often above the boiling point of liquid nitrogen (-196 °C or 77 K), which makes…
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Oersted (Unit)
Introduction The Oersted (Oe) is a unit of magnetic field strength in the centimeter-gram-second (CGS) system of units. Named after the Danish physicist Hans Christian Ørsted, this unit has been widely used in the field of magnetism. Definition and Measurement Magnetic Field Strength Magnetic field strength, also known as magnetic field intensity, is a measure…
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Cauchy-Riemann Equations
Introduction The Cauchy-Riemann equations are a pair of partial differential equations which provide necessary and sufficient conditions for a complex function to be holomorphic. A holomorphic function is complex differentiable, i.e., it is a function that is differentiable when regarded as a function on the real plane . Complex Functions and Differentiability A complex function…
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Dot Product
Introduction The dot product, also known as the scalar product, is a fundamental operation in the field of vector algebra. It operates on two vectors to produce a scalar, or single number. Definition of the Dot Product For two vectors and , the dot product is defined as: This operation multiplies corresponding components of and…