Medical research

Brown and white body fat speak different languages

Many people might not realize that they have different types of body fat. Most of it is white fat that sits on your stomach, hips and thighs, for example. White fat is an energy storage that our body can use when food is ...

Oncology & Cancer

A partnership to tackle childhood cancers in developing countries

The International Atomic Energy Agency (IAEA) and St. Jude Children's Research Hospital are joining forces to combat childhood cancers in developing countries, where children are four times more likely to die of the disease ...

Medical research

Failure of mitochondrial quality control causes heart disease

Mutations in the gene that encodes a protein called adenine nucleotide translocator (ANT) cause a variety of conditions, such as heart disease and weakness of the eye muscles, but the underlying mechanism of how these mutations ...

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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