Characteristics of heat radiation
Heat radiation has the following characteristics
① The radiant energy can be freely transmitted through a vacuum without any intermediate medium;
② All objects whose temperature is higher than 0K can continuously emit radiant energy and can also continuously absorb radiant energy from other objects;
③ Thermal radiation not only has the transfer of energy, but also has the conversion of energy form. Converted from thermal energy to radiant energy when emitted, and converted from radiant energy to thermal energy when absorbed.