News tagged with energy

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

Microreactor replaces animal testing

Researchers all over Europe are working on alternatives to animal testing that can be used to evaluate the adverse side-effects of medications. But many of these test methods still present problems. A microreactor developed ...

Feb 02, 2016
popularity92 comments 0

Study gets to the heart of heart failure

A failing heart is said to be like an "engine out of fuel." To better understand the problem of energy production in heart-failure patients, researchers at Yale University and Duke University studied the underlying metabolic ...

Jan 29, 2016
popularity3 comments 0

Why you won't lose weight with exercise alone

Exercise by itself isn't always enough to take off the weight. Now, evidence reported in the Cell Press journal Current Biology on January 28 helps to explain why that is: our bodies adapt to higher activity levels, so that ...

Jan 28, 2016
popularity290 comments 1

Team deciphers sugar's siren song

Sugar's sweetness and calorie content combine to give it lethal power to destroy diets, many scientists have assumed. However, new study by Yale University researchers says the brain responds to taste and calorie counts in ...

Jan 25, 2016
popularity53 comments 0

Brain receptor regulates fat burning in cells

Scientists at the Gladstone Institutes have discovered an unusual regulator of body weight and the metabolic syndrome: a molecular mechanism more commonly associated with brain cells. Lowering levels of P75 neurotrophin receptor ...

Jan 12, 2016
popularity190 comments 0

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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