Which one of the following constants is not related to radiation?

مندرجہ ذیل میں سے کون سا مستقل تابکاری سے متعلق نہیں ہے؟

Boltzmann’s constant

Solar constant

Stefan’s constant

None of these

Boltzmann's constant is primarily related to thermodynamics and kinetic theory, not directly to radiation.

Solar, Stefan’s, and Wien’s are directly associated with radiation laws and phenomena.