Category: Index
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Yarkovsky Effect
Introduction The Yarkovsky Effect is the force acting on a rotating body in space caused by the anisotropic emission of thermal photons (which carry momentum). This effect is named after the engineer Ivan Osipovich Yarkovsky, who first proposed the idea. This effect plays a significant role in the dynamics of small celestial bodies, such as…
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X-Rays
Introduction X-rays are a form of electromagnetic radiation with wavelengths ranging from about 10 nanometers to 0.01 nanometers, corresponding to frequencies in the range 30 petahertz () to 30 exahertz (), and energies in the range 100 eV to 100 keV. X-rays are highly penetrating and are widely used in medical imaging and in various…
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Wave Function
Introduction The wave function, denoted by the Greek letter psi (), is a mathematical function that describes the quantum state of a physical system. It provides the probabilities of the outcomes of measurements of physical quantities such as position, momentum, and energy. Schrödinger Equation The evolution of the wave function in time is governed by…
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Uncertainty Principle
Introduction The Uncertainty Principle, or Heisenberg’s Uncertainty Principle, is a fundamental concept in quantum mechanics. It states that it is impossible to precisely measure the exact position and momentum of a particle simultaneously. Uncertainty Principle Explained The mathematical formulation of the uncertainty principle is: where: This inequality means that the product of the uncertainties in…
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Time Dilation
Introduction Time dilation is a fundamental concept in physics that originates from Albert Einstein’s theory of relativity. It describes how the perception of time can vary for two observers depending on their relative motion and gravitational field. Time Dilation in Special Relativity In special relativity, time dilation occurs between two observers if one is moving…
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Mass-Energy Equivalence
Introduction Mass-energy equivalence is a fundamental principle of modern physics, stating that mass and energy are interchangeable. It’s the foundation of nuclear reactions and the idea behind nuclear power and weapons. Einstein’s Famous Equation Albert Einstein, in his Special Theory of Relativity, expressed the principle of mass-energy equivalence with the equation: where: Conceptual Understanding According…
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Radioactive Decay
Introduction Radioactive decay, also known as nuclear decay or radioactivity, is a spontaneous process in which an unstable atomic nucleus loses energy by emitting radiation. This can include alpha particles, beta particles, gamma rays, or other particles. Definition and Equation In radioactive decay, a parent nucleus transforms into a daughter nucleus and in the process…
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Ohm’s Law
Introduction Ohm’s law is a fundamental principle in the field of electronics and electrical engineering. Named after the German physicist Georg Simon Ohm, it describes how current, voltage, and resistance interact in an electrical circuit. Definition and Equation Ohm’s law states that the current flowing through a conductor between two points is directly proportional to…
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Nuclear Fusion
Introduction Nuclear fusion is a process where two light nuclei combine to form a single, heavier nucleus. It’s the same process that powers the sun and other stars. This process releases a significant amount of energy due to the difference in binding energy between the initial and final products. Definition and Equation The general equation…
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Nuclear Fission
Introduction Nuclear fission is a nuclear reaction or a radioactive decay process in which the nucleus of an atom splits into two or more smaller, lighter nuclei. This process often releases a large amount of energy and usually one or more neutrons. Definition and Equation The nuclear fission reaction can be written generally as: where:…