Using DNA templates to harness the sun's energy

As the world struggles to meet the increasing demand for energy, coupled with the rising levels of CO2 in the atmosphere from deforestation and the use of fossil fuels, photosynthesis in nature simply cannot keep up with ...

A breakthrough in the study of laser/plasma interactions

A new 3-D particle-in-cell (PIC) simulation tool developed by researchers from Lawrence Berkeley National Laboratory and CEA Saclay is enabling cutting-edge simulations of laser/plasma coupling mechanisms that were previously ...

Veritable powerhouses—even without DNA

Whether human beings or animals, plants or algae: the cells of most life forms contain special structures that are responsible for energy production. Referred to as mitochondria, they normally have their own genetic material, ...

Rapid destruction of Earth-like atmospheres by young stars

The discoveries of thousands of planets orbiting stars outside our solar system has made questions about the potential for life to form on these planets fundamentally important in modern science. Fundamentally important for ...

Simple sea anemones not so simple after all

The tube-dwelling anemone is an ancient sea creature that resembles a prehistoric flower. The animals live slow, long and predictable lifestyles and look fairly similar from species to species.

How slippery surfaces allow sticky pastes and gels to slide

An MIT research team that has already conquered the problem of getting ketchup out of its bottle has now tackled a new category of consumer and manufacturing woe: how to get much thicker materials to slide without sticking ...

New technique produces longer-lasting lithium batteries

The grand challenge to improve energy storage and increase battery life, while ensuring safe operation, is becoming evermore critical as we become increasingly reliant on this energy source for everything from portable devices ...

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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