Engineering

Sweet victory: Sensor detects adulteration in honey

Adulteration is a bitter truth in the sweet world of honey. As consumers seek nature's nectar for its purity and health benefits, a shadowy industry taints this golden elixir with hidden additives, most commonly water.

Engineering

Solar cell material can assist self-driving cars in the dark

Material used in organic solar cells can also be used as light sensors in electronics. This has been shown by researchers at Linköping University, Sweden, who have developed a type of sensor able to detect circularly polarized ...

Hardware

Researchers 3D print a miniature vacuum pump

Mass spectrometers are extremely precise chemical analyzers that have many applications, from evaluating the safety of drinking water to detecting toxins in a patient's blood. But building an inexpensive, portable mass spectrometer ...

Robotics

Magnetic microrobot can measure both cell stiffness and traction

Scientists have developed a tiny mechanical probe that can measure the inherent stiffness of cells and tissues as well as the internal forces the cells generate and exert on one another. Their new "magnetic microrobot" is ...

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Electromagnetic field

The electromagnetic field is a physical field produced by electrically charged objects. It affects the behavior of charged objects in the vicinity of the field.

The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction. It is one of the four fundamental forces of nature (the others are gravitation, the weak interaction, and the strong interaction). The field propagates by electromagnetic radiation; in order of increasing energy (decreasing wavelength) electromagnetic radiation comprises: radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

The field can be viewed as the combination of an electric field and a magnetic field. The electric field is produced by stationary charges, and the magnetic field by moving charges (currents); these two are often described as the sources of the field. The way in which charges and currents interact with the electromagnetic field is described by Maxwell's equations and the Lorentz force law.

From a classical perspective, the electromagnetic field can be regarded as a smooth, continuous field, propagated in a wavelike manner; whereas, from a quantum mechanical perspective, the field is seen as quantised, being composed of individual particles.

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