The EM spectrum
Electromagnetic (EM) radiation may be a kind of energy that travels in waves at a speed of 186,000 miles (300,000 km) per second, that is that the quickest speed within the universe. Totally different forms of radiation form up the EM spectrum. Every kind of radiation except actinic ray area unit invisible.
The EM spectrum is created of seven major varieties of radiation, that vary within the length of their waves. The shorter the radiation’s wavelength, the upper its energy. The longest waves are often several miles long, whereas the shortest area unit shorter than one atom.
Sunlight contains ultraviolet (UV) rays.
Goggles, sunglasses, and sun screen defend the eyes and skin from actinic ray rays, which may be harmful.
Gamma rays have the best energy of all. Observatories live gamma rays emitted by extremely popular stars and different bodies in area.
X-rays have enough energy to suffer several materials. They’re accustomed scan the contents of luggage at security checks.
Radio waves have the longest wavelength. Radio and television broadcasts and Wi-Fi use radio waves.
Microwaves area unit accustomed heat food. They’re conjointly employed by cell phones.