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 ...

Energy & Green Tech

How much energy do we really need?

Two fundamental goals of humanity are to eradicate poverty and reduce climate change, and it is critical that the world knows whether achieving these goals will involve trade-offs. New IIASA research for the first time provides ...

Software

Software helps planners design walkable cities

Walkable cities reduce traffic congestion, which causes around 3.3 million deaths and $121 billion in economic losses every year. But when architects are developing pedestrian-friendly neighborhoods, they often rely on trial ...

Computer Sciences

Modeling every building in America starts with Chattanooga

Buildings use 40 percent of America's primary energy and 75 percent of its electricity, which can jump to 80 percent when a majority of the population is at home using heating or cooling systems and the seasons reach their ...

Energy & Green Tech

Harvesting energy from walking human body

A research team led by Professor Wei-Hsin Liao from the Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong (CUHK) has developed a lightweight smart materials-based energy harvester for ...

Automotive

Aston Martin unveils first SUV, eyes luxury buyers in China

British carmaker Aston Martin unveiled its first-ever sports utility vehicle (SUV) Wednesday at events in Beijing and Los Angeles, signalling it was banking on China's growing appetite for luxury to prop up sales.

Engineering

Li-ion battery components to be printed on an inkjet printer

Scientists from Peter the Great St.Petersburg Polytechnic University (SPbPU) are developing a technology for printing the electrodes for miniature li-ion batteries using an inkjet printer. The ongoing research may help to ...

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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