The surface that absorbs all radiant energy that falls on it is known as a black body. The incident visible light will be absorbed rather than reflected, therefore the surface will appear black. The best practical example of a blackbody is a small hole in a box with a blackened interior. A blackbody in thermal equilibrium emits electromagnetic radiation called black body radiation. The emitted radiation has a spectrum that is determined by the temperature alone, not by the body’s shape or composition.
98% of the incident radiation is absorbed by a blackbody. Polished metal surfaces, on the other hand, absorb only about 6 per cent of the incident radiation, reflecting the rest.