Pediatrics

Why fidgeting could be good for your child's health

Fidgeting is usually considered as a sign of boredom or lack of attention which can be distracting to others. Parents and teachers often demand that their children and pupils stop doing it. But fidgeting could actually be ...

Obstetrics & gynaecology

The benefits of strength training during pregnancy

For most healthy women, exercise during pregnancy is as important as it is at all times of life. It brings benefits such as better overall health, preventing back pain and keeping you regular, which can be a challenge for ...

Health

Tiring easily may warn of future heart trouble

Fatigue is universal, a feeling that becomes increasingly familiar as people get older. But when you fatigue too easily, it may not just be related to age but a reflection of your chance of having a stroke or heart attack ...

Medical research

Preclinical research suggests anti-cancer effect of keto diet

It's well known that keeping blood glucose levels in check can help individuals avoid or manage diabetes, but new research led by biologists at The University of Texas at Dallas suggests that restricting blood glucose levels ...

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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