Black Body Radiation

[Alexander23]

I was wondering how/why the emitted radiation is not dependent on the substance, but rather on it's temperature in the black body model? (does this contradict the work done by Bohr and the unique spectral lines?)
Also, how did the classical physics explanation not obey the law of conservation of energy?

Thankss

[jamonwindeyer]

I was wondering how/why the emitted radiation is not dependent on the substance, but rather on it's temperature in the black body model? (does this contradict the work done by Bohr and the unique spectral lines?)
Also, how did the classical physics explanation not obey the law of conservation of energy?

Thankss

Hey Alexander! Welcome to the forums!!  let me know if you need any help finding anything 

To answer your first question, it's because the emission of black body radiation is due to the thermal vibrations of the black body. When objects get hot, they vibrate, and it is these vibrations that emit the black body radiation (specifics are not assessable)  These vibrations are not dependent on substance, only on temperature. Although different substances will obviously heat up faster, or typically be hotter, but that is not what effects black body radiation. A bowling ball heated to the temperature of the sun will have the same black body radiation curve as the sun 

The classical physics explanation (based on something called Rayleigh Jeans Law) predicted that the intensity of black body radiation would increase at higher frequencies, actually approaching infinity! Obviously, we can't have infinite intensity, because that means infinite energy, and thus it violates the Conservation of Energy 

[Alexander23]

Thanks a lot