A blackbody is an idealized object. Real objects will not absorb all wavelengths equally.pkc111 said:Why are some materials behave more like black-bodies than others?
It means 100% absorption at any wavelength (no reflection). Perfect emission corresponds to the blackbody spectrum.pkc111 said:What does it mean a "perfect" radiator and absorber?
Yes, but an actual object will not emit following the exact blackbody curve. Some wavelengths will be favored with respect to others.pkc111 said:All objects give off 100% of the heat energy given to them eventually if they are at the same temperature as their environment...right?
A "perfect" radiator or absorber is one that is able to efficiently emit or absorb thermal radiation at all wavelengths. This means that it has a high emissivity or absorptivity across the entire electromagnetic spectrum.
Materials differ in their ability to radiate or absorb heat based on their physical properties, such as their composition, structure, and surface properties. For example, materials with higher atomic/molecular vibrations or larger surface area tend to have higher emissivity or absorptivity.
Some examples of materials with high emissivity include black surfaces, such as carbon or soot, as well as metals like copper or aluminum. Materials with high absorptivity include dark-colored surfaces, such as black paint or fabric, as well as materials with rough or textured surfaces.
Yes, the emissivity or absorptivity of a material can be changed by altering its physical properties. For example, the surface of a material can be roughened or coated to increase its emissivity or absorptivity. However, these changes may also affect other properties of the material, such as its reflectivity or conductivity.
Understanding the difference in materials' radiative properties is important for various applications, such as designing energy-efficient buildings or developing thermal management systems for electronic devices. It can also help in the design and optimization of materials for specific purposes, such as solar energy harvesting or thermal insulation.