The Stefan-Boltzmann law, which includes the Stefan-Boltzmann constant, primarily applies to which type of bodies? 

Explanation:

Stefan-Boltzmann Law

• The Stefan-Boltzmann law is a fundamental principle in thermal radiation that describes the power radiated from a black body in terms of its temperature. The law is named after physicist Josef Stefan, who experimentally established the law in 1879, and Ludwig Boltzmann, who derived it theoretically.
• The law states that the total energy radiated per unit surface area of a black body is directly proportional to the fourth power of the black body's absolute temperature. This implies that even a small increase in temperature results in a significant increase in the amount of radiation emitted.

Mathematical Expression: The Stefan-Boltzmann law is mathematically expressed as:

J = σT⁴

Where:

• J is the total power radiated per unit surface area of the black body.
• σ is the Stefan-Boltzmann constant, approximately equal to 5.67 × 10^-8 W/m²K⁴.
• T is the absolute temperature of the black body in Kelvin (K).

Option 2: Black bodies

• This option correctly identifies the type of bodies to which the Stefan-Boltzmann law primarily applies. A black body is an idealized physical body that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence. Because of this property, a black body is also the best emitter of thermal radiation. The Stefan-Boltzmann law applies specifically to black bodies, which radiate energy according to the formula J = σT⁴.