List the types of electromagnetic radiation in order of decreasing energy per photon.
(a) gamma rays
(b) radio waves
(d) visible light
Electromagnetic (EM) radiation is the movement of energy - through space or a medium - composed of both electric and magnetic waves. These waves oscillate at frequencies that can vary from a few cycles per second (hertz) to more than 1020 hertz.
Example:radio waves, microwaves, X-rays and gamma rays. Sunlight is also a form of EM energy, but visible light is only a small portion of the EM spectrum, which contains a broad range of electromagnetic wavelengths.