News tagged with energy

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

Choosing colorful, healthy foods

Dear Mayo Clinic: I notice a lot of food products, including cereals, no longer use artificial colors. Is this because food dyes are harmful?

Oct 13, 2017
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Identifying ways to minimize the harm of energy drinks

Because many countries allow the sale of energy drinks to young people, identifying ways to minimize potential harm from energy drinks is critical. A new study published in the Journal of Nutrition Education and Behavior ...

Oct 05, 2017
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Black tea may help with weight loss, too

UCLA researchers have demonstrated for the first time that black tea may promote weight loss and other health benefits by changing bacteria in the gut. In a study of mice, the scientists showed that black tea alters energy ...

Oct 03, 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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