Hardware

Advances in AI, chips boost voice recognition

Separate developments in speech recognition technology from IBM and California universities at San Francisco and Berkeley offer promising news for patients suffering from vocal paralysis and speech loss.

Energy & Green Tech

Nanofluidic device generates power with saltwater

There is a largely untapped energy source along the world's coastlines: the difference in salinity between seawater and freshwater. A new nanodevice can harness this difference to generate power.

Business

Predicting the sustainability of a future hydrogen economy

As renewable energy sources like wind and solar ramp up, they can be used to sustainably generate hydrogen fuel. But implementing such a strategy on a large scale requires land and water dedicated to this purpose.

Energy & Green Tech

New approach may help extract more heat from geothermal reservoirs

Geothermal heat offers a promising source of renewable energy with almost zero emissions, but it remains a relatively expensive option to generate electricity. A new technique proposed by Penn State scientists may help prevent ...

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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