Question

State : (a) Wien's displacement law, and (b) first law of thermodynamics.

Answer 1

(a) According to Wein's displacement law, as the temperature of a black body rises, the peak of the distribution curve shifts towards the shorter wavelength $\left(\lambda \right)$.
Thus, ${\lambda }_{m}T=b$ (constant) where $b=2.9\times {10}^{-3}mK$.
(b) The first law of thermodynamics, between any two states of equilibrium, the change in internal energy is equal to the difference of the heat transfer into the system and work done by the system. Thus, in simpler terms, energy can be changed from one form to another but it cannot be created or destroyed. Hence, energy is always conserved.