Energy & Green Tech

Dye-sensitized solar cells that adapt to different light conditions

Solar cells made of semi-transparent photovoltaic (PV) materials typically have a fixed optical transmission, which results in either high transparency or high efficiency, but rarely both. In order to perform optimally when ...

Robotics

An origami-based robotic structure inspired by ladybird wings

Researchers at Seoul National University have recently developed a compact and lightweight origami structure inspired by ladybird beetles. In a paper published in Science Robotics they show how this structure can be used ...

Robotics

A flexible microrobot that can survive almost any deformation

An International research team led by Dr. Oliver Schmidt, working at Chemnitz University of Technology (TU Chemnitz) and Leibniz IFW Dresden has recently developed a microrobitic system with a wide range of possible applications, ...

Telecom

A scheme for hybrid access point (H-AP) deployment in smart cities

Researchers at the University of Essex, UESTC-China and ZTE have recently introduced a scheme for the deployment of hybrid access points (H-APs), which could simultaneously enable wireless information transfer (WIT) and wireless ...

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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