Robotics

Robotic lightning bugs take flight

Fireflies that light up dusky backyards on warm summer evenings use their luminescence for communication—to attract a mate, ward off predators or lure prey.

Electronics & Semiconductors

New tech can double spectral bandwidth in some 5G systems

Some materials, like wood, are insulators that block the flow of electricity. Conductors, such as copper, allow for electricity to flow through them. Other materials—semiconductors—can be either/or depending on conditions ...

Energy & Green Tech

Future electric cars could recharge wirelessly while you drive

Electric vehicles may one day be able to recharge while driving down the highway, drawing wireless power directly from plates installed in the road that would make it possible to drive hundreds—if not thousands—of miles ...

Robotics

New prototype exoskeletons for industrial workers

Researchers at IIT-Istituto Italiano di Tecnologia (Italian Institute of Technology) and INAIL (Italian Worker's Compensation Authority) have designed and created innovative prototypes of wearable robotic exoskeletons for ...

Consumer & Gadgets

Wireless electricity and safety

A wireless power system developed by researchers at the University of Tokyo and University of Michigan can power cell phones, lights and other devices by using magnetic fields to deliver electricity over the air. A recent ...

Consumer & Gadgets

Tracking sleep with a self-powering smart pillow

The human body needs sleep as much as it needs food and water. Yet many people fail to get enough, causing both mind and body to suffer. People who struggle for shut-eye could benefit from monitoring their sleep, but they ...

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Electric field

In physics, the space surrounding an electric charge or in the presence of a time-varying magnetic field has a property called an electric field. This electric field exerts a force on other electrically charged objects. The concept of an electric field was introduced by Michael Faraday.

The electric field is a vector field with SI units of newtons per coulomb (N C−1) or, equivalently, volts per metre (V m−1). The SI base units of the electric field are kg·m·s−3·A−1. The strength of the field at a given point is defined as the force that would be exerted on a positive test charge of +1 coulomb placed at that point; the direction of the field is given by the direction of that force. Electric fields contain electrical energy with energy density proportional to the square of the field intensity. The electric field is to charge as gravitational acceleration is to mass and force density is to volume.

A moving charge has not just an electric field but also a magnetic field, and in general the electric and magnetic fields are not completely separate phenomena; what one observer perceives as an electric field, another observer in a different frame of reference perceives as a mixture of electric and magnetic fields. For this reason, one speaks of "electromagnetism" or "electromagnetic fields." In quantum mechanics, disturbances in the electromagnetic fields are called photons, and the energy of photons is quantized.

This text uses material from Wikipedia, licensed under CC BY-SA