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Physics

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Sports, Science

Ronald McNair

Ronald Erwin McNair was an American NASA astronaut and physicist. He died during the launch of the Space Shuttle Challenger on mission STS-51-L, in which he was serving as one of three mission specialists in a crew of seven.

Art, Technology and industry, Science

Albert Einstein

Albert Einstein was a German-born theoretical physicist who developed the theory of relativity, one of the two pillars of modern physics. His work is also known for its influence on the philosophy of science. He is best known to the general public for his mass–energy equivalence formula , which has been dubbed "the world's most famous equation". He received the 1921 Nobel Prize in Physics "for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect", a pivotal step in the development of quantum theory.

Science

Planck constant

The Planck constant is a physical constant that is the quantum of action, central in quantum mechanics.

Science

Marie Curie

Marie Skłodowska Curie was a Polish and naturalized-French physicist and chemist who conducted pioneering research on radioactivity. She was the first woman to win a Nobel Prize, the first person and only woman to win the Nobel prize twice, and the only person to win the Nobel Prize in two different scientific fields. She was part of the Curie family legacy of five Nobel Prizes. She was also the first woman to become a professor at the University of Paris, and in 1995 became the first woman to be entombed on her own merits in the Panthéon in Paris.

Music, TV, Business and economy, Science

Brian Cox (physicist)

Brian Edward Cox is an English physicist who serves as professor of particle physics in the School of Physics and Astronomy at the University of Manchester. He is best known to the public as the presenter of science programmes, especially the Wonders of... series and for popular science books, such as Why Does E=mc²? and The Quantum Universe. He has been the author or co-author of over 950 scientific publications.

Science

Quantum mechanics

Quantum mechanics, including quantum field theory, is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.

Science

Dew point

The dew point is the temperature to which air must be cooled to become saturated with water vapor. When further cooled, the airborne water vapor will condense to form liquid water (dew). When air cools to its dew point through contact with a surface that is colder than the air, water will condense on the surface. When the temperature is below the freezing point of water, the dew point is called the frost point, as frost is formed rather than dew. The measurement of the dew point is related to humidity. A higher dew point means there will be more moisture in the air.

Science

Aurora

An aurora, sometimes referred to as polar lights, northern lights or southern lights, is a natural light display in the Earth's sky, predominantly seen in the high-latitude regions.

Science

C. V. Raman

Sir Chandrashekhara Venkata Raman was an Indian Tamil physicist born in the former Madras Province in India presently the state of Tamil Nadu, who carried out ground-breaking work in the field of light scattering, which earned him the 1930 Nobel Prize for Physics. He discovered that when light traverses a transparent material, some of the deflected light changes wavelength and amplitude. This phenomenon, subsequently known as Raman scattering, results from the Raman effect. In 1954, Indian government honoured him with India's highest civilian award, the Bharat Ratna.

Science

Gravity

Gravity, or gravitation, is a natural phenomenon by which all things with mass or energy—including planets, stars, galaxies, and even light—are brought toward one another. On Earth, gravity gives weight to physical objects, and the Moon's gravity causes the ocean tides. The gravitational attraction of the original gaseous matter present in the Universe caused it to begin coalescing, forming stars – and for the stars to group together into galaxies – so gravity is responsible for many of the large scale structures in the Universe. Gravity has an infinite range, although its effects become increasingly weaker on farther objects.

Science

Theory of relativity

The theory of relativity usually encompasses two interrelated theories by Albert Einstein: special relativity and general relativity. Special relativity applies to elementary particles and their interactions, describing all their physical phenomena except gravity. General relativity explains the law of gravitation and its relation to other forces of nature. It applies to the cosmological and astrophysical realm, including astronomy.

Science

Speed of light

The speed of light in vacuum, commonly denoted c, is a universal physical constant important in many areas of physics. Its exact value is 299,792,458 metres per second. It is exact because by international agreement a metre is defined to be the length of the path travelled by light in vacuum during a time interval of 1/299792458 second. According to special relativity, c is the maximum speed at which all conventional matter and hence all known forms of information in the universe can travel. Though this speed is most commonly associated with light, it is in fact the speed at which all massless particles and changes of the associated fields travel in vacuum. Such particles and waves travel at c regardless of the motion of the source or the inertial reference frame of the observer. In the special and general theories of relativity, c interrelates space and time, and also appears in the famous equation of mass–energy equivalence E = mc2.

Nature and flora, Science

Rainbow

A rainbow is a meteorological phenomenon that is caused by reflection, refraction and dispersion of light in water droplets resulting in a spectrum of light appearing in the sky. It takes the form of a multicoloured circular arc. Rainbows caused by sunlight always appear in the section of sky directly opposite the sun.

Art, Science

Sally Ride

Sally Kristen Ride was an American engineer, physicist and astronaut. Born in Los Angeles, she joined NASA in 1978 and became the first American woman in space in 1983. Ride was the third woman in space overall, after USSR cosmonauts Valentina Tereshkova (1963) and Svetlana Savitskaya (1982). Ride remains the youngest American astronaut to have traveled to space, having done so at the age of 32. After flying twice on the Orbiter Challenger, she left NASA in 1987. She worked for two years at Stanford University's Center for International Security and Arms Control, then at the University of California, San Diego as a professor of physics, primarily researching nonlinear optics and Thomson scattering. She served on the committees that investigated the Challenger and Columbia space shuttle disasters, the only person to participate in both. Ride died of pancreatic cancer on July 23, 2012.

Science

Quantum entanglement

Quantum entanglement is a physical phenomenon which occurs when pairs or groups of particles are generated, interact, or share spatial proximity in ways such that the quantum state of each particle cannot be described independently of the state of the other(s), even when the particles are separated by a large distance—instead, a quantum state must be described for the system as a whole.