light bulb printable

Light, visible light, or visible radiation is electromagnetic radiation that can be perceived by the human eye. [1][2] Visible light spans the visible spectrum and is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 terahertz. Light is a primary tool for perceiving the world and interacting with it for many organisms. Light from the Sun warms the Earth, drives global weather patterns, and initiates the life-sustaining process of photosynthesis; about 10 22 joules of solar radiant energy reach Earth each day. Light is a transverse, electromagnetic wave that can be seen by a typical human. Wavelengths in the range of 400–700 nm are normally thought of as light. In his formulation of electromagnetism, Maxwell described light as a propagating wave of electric and magnetic fields. More generally, he predicted the existence of electromagnetic radiation: coupled electric and magnetic fields traveling as waves at a speed equal to the known speed of light. Visible light is but one example of a much broader set of phenomena—an electromagnetic spectrum with no theoretical upper or lower limit to frequencies and wavelengths.

In common usage, the term light (or visible light) refers to electromagnetic radiation in a wavelength range that is visible to the human eye (about 400–700 nanometers (nm) (15.7-27.6 millionths of an inch)). Rays, or beams of light shine through metal patterns into a railway station. Light is a form of electromagnetic radiation. It is natural agent that stimulates sight and makes things easy to see. Light is the opposite of darkness. Light has a wavelength. Some wavelengths can be seen by the human eye. Others cannot. [1] . Many animals can see light.