News tagged with energy

Related topics: electricity · energy consumption · renewable energy · energy efficiency · fossil fuels

What exercises burn the most calories?

Researchers from Universidad Politécnica de Madrid (UPM) have calculated for the first time the real energy expenditure in different training programs, including both aerobic and anaerobic forms.

Feb 20, 2017
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Metabolism drives growth and division of cancer cells

The metabolic state of tumor cells contributes to signals that control their proliferation. German biochemist and Nobel Prize laureate Otto H. Warburg observed in the 1920s that tumor cells radically change their metabolism. ...

Feb 20, 2017
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Vitamin B3 prevents glaucoma in laboratory mice

In mice genetically predisposed to glaucoma, vitamin B3 added to drinking water is effective at preventing the disease, a research team led by Jackson Laboratory Professor and Howard Hughes Medical Investigator Simon W.M. ...

Feb 16, 2017
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Energy

In physics, energy (from the Greek ἐνέργεια - energeia, "activity, operation", from ἐνεργός - energos, "active, working") is a scalar physical quantity that describes the amount of work that can be performed by a force, an attribute of objects and systems that is subject to a conservation law. Different forms of energy include kinetic, potential, thermal, gravitational, sound, light, elastic, and electromagnetic energy. The forms of energy are often named after a related force.

Any form of energy can be transformed into another form, but the total energy always remains the same. This principle, the conservation of energy, was first postulated in the early 19th century, and applies to any isolated system. According to Noether's theorem, the conservation of energy is a consequence of the fact that the laws of physics do not change over time.

Although the total energy of a system does not change with time, its value may depend on the frame of reference. For example, a seated passenger in a moving airplane has zero kinetic energy relative to the airplane, but non-zero kinetic energy relative to the Earth.

This text uses material from Wikipedia, licensed under CC BY-SA

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