Medical research

New research raises prospect of better anti-obesity drugs

Effective weight-loss strategies call for eating less food, burning more calories—or ideally, both. But for the more than 90 million Americans who suffer from obesity, a disease that contributes to conditions ranging from ...

Medical research

Exercise may have different effects in the morning and evening

Researchers from the University of Copenhagen have learned that the effect of exercise may differ depending on the time of day it is performed. In mice, they demonstrate that exercise in the morning results in an increased ...

Neuroscience

Obesity: The key role of a brain protein revealed

Regardless of how much you exercise or how balanced your diet is, controlling your weight is more brain-related than you might have thought. In a study published in the Journal of Clinical Investigation, researchers from ...

Medical research

A link between mitochondrial damage and osteoporosis

Some risk factors for osteoporosis such as being older and female or having a family history of the condition cannot be avoided. But others can, like smoking cigarettes, consuming alcohol, taking certain medications, or being ...

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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