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Boson

A boson is a particle which carries a force. It has a whole number spin. Bosons carry energy. A photon is an example of a boson as it has a spin of 1 and carries electromagnetism. Mesons are also bosons as they carry nuclear force. Bosons are dif ...

                                               

Cavity magnetron

The cavity magnetron is a high-powered vacuum tube that makes microwaves using the interaction of a stream of electrons with a magnetic field. Electrons pass by holes, and the resonance creates microwaves, like blowing air on a flute creates soun ...

                                               

Chemical potential

Chemical Potential Energy is the energy stored up in substances due to their chemical bonds. It is energy that is stored in chemicals. One example of how this plays a part in real life is through plants. The plants make energy with chemical poten ...

                                               

Composite particle

Composite particles are subatomic particles that are made of more than one quark. Simple particles like protons are actually composites of multiple quarks. Protons are known as baryons, which means that they are made of exactly three quarks. Bary ...

                                               

Conduction

Conduction in physics is about forms of energy, namely heat or electricity. Heat conduction takes place between two objects in contact with each other. Heat energy moves from one to the other. In heat conduction, the heat energy travels from the ...

                                               

Conservation of mass

The law of conservation of mass states that mass can neither be created nor destroyed in a chemical reaction. Thus, the amount of matter cannot change. Sir Antoine Lavoisier promoted this idea. This law says that when a chemical reaction rearrang ...

                                               

Crest (physics)

A crest is the point on a wave with the greatest positive value or upward displacement in a cycle. A trough is the opposite of a crest. When the crest and the trough of two waves of equal magnitude and frequency intersect or collide when in phase ...

                                               

Critical density

Critical density is the value at which the Universe is at balance, and expansion is stopped. This value is estimated as ×10^-26 kg/m³ and it’s calculated when you take the matter-energy density of the universe and divide it by the matter-energy d ...

                                               

Deneb

Deneb is the brightest star in the constellation of Cygnus. It, along with Vega, and Altair make up the Summer Triangle asterism. It has an apparent magnitude of 1.25, which means that it is the 20th brightest star in the night sky. However its d ...

                                               

Desublimation

Desublimation is a phase transition in which gas turns into solid without passing through the liquid state. It is the reverse of sublimation. It is how snow forms in clouds, and how frost and hoar frost form on the ground or on windows. Another e ...

                                               

Dirac equation

The Dirac equation is an equation from quantum mechanics. Paul Dirac formulated the equation in 1928. The equation describes the behaviour of fermions, and takes special relativity into account. The equation showed the existence of antimatter. It ...

                                               

Drag (physics)

In fluid dynamics, drag is a force which tends to slow the movement of an object through a liquid or gas. As a moving object pushes the liquid or gas out of its way, the fluid pushes back on the object. This drag force is always opposite to the o ...

                                               

Electric field

An electric field is a vector field that shows the direction that a positively charged particle will move when placed in the field. More precisely, if a particle has an electric charge q {\displaystyle q} and is in an electric field E → {\display ...

                                               

Electric power

Electric power is defined as the power dissipated by an electric circuit. Electric power is a measurement of the rate at which energy is used over a period of time. The SI unit for power is the watt, the unit for energy is the joule, and the unit ...

                                               

Electrical conductor

A conductor is a material which electricity, heat or sound can flow through. An electrical conductor conducts electricity. The ability to conduct electricity is called electrical conductivity. Most metals, like iron and copper, are electrical con ...

                                               

Electron cloud

Electron cloud is an informal way to describe an atomic orbital. The electron cloud is not really a thing. An electron cloud model is different from the older Bohr atomic model by Niels Bohr. Bohr talked about electrons orbiting the nucleus. Expl ...

                                               

Energy (society)

The use of energy is important to human society for handling problems in the environment. Developed societies use energy resources for agriculture, transportation, garbage collection, information technology and human communication. The use of ene ...

                                               

Escape velocity

Escape velocity is the initial speed that something would need to completely escape the gravity of a large body, like a star or a planet, by mere inertia. If a ball is thrown upwards while standing on the ground, the ball will reach a certain hei ...

                                               

Faradays law of induction

Faradays law of induction is a law of physics proposed by English physicist Michael Faraday in 1831. It is one of the basic laws of electromagnetism. The law explains why generators, transformers and electrical motors work. Faradays law of induct ...

                                               

Fluid

A fluid is a substance that can move easily and change shape such as water, or air, or plasmas. They can flow- flow and fluids both come from the same English word roots and are pronounced similarly. The physics of fluids is called fluid mechanic ...

                                               

Gausss law

Gausss law is a law of physics. The law is about the relationship between electric charge and the resulting electric field. In words, Gausss law states that: The net electric flux through any closed surface is equal to ​ 1 ⁄ ε times the net elect ...

                                               

Gravitational constant

The gravitational constant, called G {\displaystyle G} in physics equations, is an empirical physical constant. It is used to show the force between two objects caused by gravity. The gravitational constant appears in Isaac Newtons universal law ...

                                               

Graviton

A graviton is a hypothetical particle that transfers gravitations force from its field. Gravitons have never been observed, directly or indirectly, however, there have been several theories that use gravitons to explain certain phenomena. For exa ...

                                               

Hadron

A hadron, in particle physics, is any subatomic particle or antiparticle which is made of quarks. Quarks are fundamental particles which among other properties have an electrical charge and a name. The electrical charge of a single quark is alway ...

                                               

Harmonic

A harmonic of a wave is the part of a signals frequency that is a whole multiple of the fundamental frequency. The fundamental frequency is the lowest frequency of a periodic waveform. If f is the fundamental frequency, then the harmonics have fr ...

                                               

Kaon

Kaons are a specific type of meson. What makes kaons unique is that they are made of one up quark or down quark, and one strange quark. The discovery of kaons was significant because it proved the existence of yet another flavour of quark, the st ...

                                               

Luminosity

Luminosity is the amount of power given off by an astronomical object. Stars, galaxies and other objects emit energy in the form of radiation. It is measured in joules per second, which are equal to watts. A watt is one unit of power. Just as a l ...

                                               

Macroscopic

Macroscopic means physical objects that are measurable and can be seen by the naked eye. When one uses macroscopic for abstract objects, one thinks of the world as we see it without any help. Lengths scales are called macroscopic if they fall in ...

                                               

Magnon

A magnon in physics is a quasiparticle with magnetic properties. It is not a thing which exists on its own in free space but exists only within the structure being studied usually a crystalline solid. Each atom in a solid has a magnetic field gen ...

                                               

Microwave

A microwave is a high-frequency radio wave. They are broadly defined as having a wavelength between 1 millimeter and 1 meter, or narrowly between 3 mm and 300 mm. Microwaves have many uses including radar, radio astronomy, and to heat food in a m ...

                                               

Motor–generator

A motor–generator is a device for converting electrical power to another form. Motor–generator sets are used to convert frequency, voltage, or phase of power. They may also be used to isolate electrical loads from the electrical power supply line ...

                                               

Neutrino

Neutrinos are a type of elementary particle that exist all across the universe. Physicists study these particles, but they are hard to find because they have a very small chance of interacting with regular matter. Neutrinos travel near the speed ...

                                               

Newtons Law of Cooling

Newtons Law of Cooling describes how the temperature of an object changes. It states that the rate of change of its temperature depends on how much hotter it is than its surroundings. Since it includes both temperature and the time derivative of ...

                                               

Nuclear magnetic resonance

Nuclear magnetic resonance is the physical phenomenon in which magnetic nuclei in a magnetic field absorb, then re-emit electromagnetic radiation. This energy is of a specific resonance frequency that depends on the magnetic field strength, and t ...

                                               

Nucleon

In physics and chemistry, a nucleon refers to any subatomic particle found in the nucleus of an atom. For instance, protons and neutrons are nucleons, since they are in the nucleus of the atom. Nucleons are made of quarks.

                                               

Oil refinery

An oil refinery or petroleum refinery is an industrial plant where crude oil is made into useful petroleum products by fractional distillation and other processes. Products include gasoline, diesel fuel, asphalt base, heating oil, kerosene, and l ...

                                               

Oil well

An oil well is a well to get petroleum from the ground. People in the petroleum industry look for a place that might have oil. They drill a hole deep in the ground and, if the oil is there, then pump it up from the hole. Most oil is very deep und ...

                                               

Particle accelerator

A particle accelerator, also called an atom smasher, is a machine that accelerates particles and makes them travel at very high speeds. Accelerators work by pushing particles like electrons, protons, or atomic nuclei with electric fields and by s ...

                                               

Pauli exclusion principle

The Pauli exclusion principle refers to the fact that certain particles cannot be at the same place at the same time, with the same energy. Only fermions are bound by the Pauli exclusion principle, while bosons are not. A more precise way to desc ...

                                               

Physical coefficient

Coefficient of Thermal Expansion thermodynamics dimensionless - Relates the change in temperature to the change in a materials dimensions. Hall coefficient electrical physics - Relates a magnetic field applied to an element to the voltage created ...

                                               

Pressurized water reactor

Pressurized water reactors form the large majority of the worlds nuclear power plants. In a PWR, the coolant is pumped under high pressure to the reactor core where it is heated by the energy released by the fission of atoms. Pressure in the prim ...

                                               

Quantum fluctuation

A quantum fluctuation is the temporary change in the amount of energy in a point in space, as explained in Werner Heisenbergs uncertainty principle. It applies only to quantum physics. That means that conservation of energy can seem to be violate ...

                                               

Quantum tunnelling

Quantum tunnelling is a part of the theoretical branch of physics known as quantum mechanics. It states that electrons can behave like both particles and waves, and can cancel the effects of an energy barrier if the energy barrier is thin enough, ...

                                               

Radiation pressure

Radiation pressure is the pressure exerted upon any surface exposed to electromagnetic radiation. If absorbed, the pressure is the energy flux density divided by the speed of light. If the radiation is totally reflected, the radiation pressure is ...

                                               

Radiometer

A radiometer or roentgenometer is a device for measuring the radiant flux of electromagnetic radiation. Generally, a radiometer is an infrared radiation detector or ultraviolet detector.

                                               

REN21

REN21, the Renewable Energy Policy Network for the 21st Century, is an organization which provides a forum for international leadership in renewable energy policy, in order to promote the rapid growth of renewable energy technologies in developin ...

                                               

Rigel

Rigel is a hot supergiant star in the Milky Way Galaxy. It is classified as a blue supergiant. It is located in the constellation Orion. Many scientists believe that Rigel is the youngest star in the constellation. Rigel is much bigger than our s ...

                                               

Roche limit

The Roche limit, sometimes referred to as the Roche radius, is the distance within which a celestial body, held together only by its own gravity, will disintegrate due to a second celestial bodys tidal forces exceeding the first bodys gravitation ...

                                               

Satellite flare

A Satellite flare is a phenomenon caused by man-made satellite where the sunlight is reflected back to Earth. This results in a quick and bright "flare." Some flares can be up to 20 times brighter than Venus. Iridium satellites are satellites tha ...

                                               

Schwarzschild radius

The Schwarzschild radius, or gravitational radius is the radius of a sphere that has certain properties: if all the mass of an object is compressed within this sphere, the escape speed from the surface of the sphere would equal the speed of light ...