Energy & Green Tech

A new water-splitting technique to generate clean hydrogen

Electrolytic hydrogen production entails the generation of hydrogen from water using electrical power, which should ideally come from renewable power sources such as sunlight and wind. Although this method of producing hydrogen ...

Consumer & Gadgets

A new non-fullerene acceptor for indoor solar energy applications

Organic photovoltaic (OPV) cells, a third-generation solar cell technology that can convert solar energy into electricity, have been found to be more efficient than silicon cells under low light intensity indoor LED illumination. ...

Engineering

A smart, self-powered ping-pong table

A team of researchers from China and the U.S. has built a smart, self-powered ping-pong table. In their paper published in the journal Nature Communications, the group describes how the table was built and how it powers itself.

Engineering

New hybrid device can both capture and store solar energy

Researchers from the University of Houston have reported a new device that can both efficiently capture solar energy and store it until it is needed, offering promise for applications ranging from power generation to distillation ...

Robotics

Chameleon's tongue strike inspires fast-acting robots

Chameleons, salamanders and many toads use stored elastic energy to launch their sticky tongues at unsuspecting insects located up to one-and-a-half body lengths away, catching them within a tenth of a second.

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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