What Is Light?

Light is a form of energy that enables us to see objects surrounding us, it causes the sensation of vision. We see object when light from a source or from a reflecting body enters our eyes. Light can be seen as a form of energy in the electromagnetic spectrum with a range in wavelength from 380 nm on the violet end to 700 nm on the red end of the visible spectrum. There is also light that is not visible to humans. The range just below 380 nm is described as ultraviolet [UV] while the range just above 700 nm is described as infrared [IR]. Even though these wavelength ranges are invisible to the human eye, they are also considered as light. Radio waves and x-rays are also considered as invisible light.

Key terms

• Light is a form of energy that enables us to see objects surrounding us, it causes the sensation of vision.