Physics help from experts.
An ideal blackbody is an object that absorbs all radiation that strikes it.
- the electromagnetic radiation emitted by a blackbody. Cool blackbodies emit mostly long wavelengths (microwave or infrared). As they heat up, blackbodies radiate more high energy (short wavelength) ultraviolet emissions.
Planck developed an equation that accurately described blackbody radiation. The equation contained a term that became interpreted to mean that particles could only vibrate with discrete amounts of energy. This is the quantum hypothesis.