State Wien’s displacement law.
The figure below shows the wavelength distributions of electromagnetic radiation emitted by two stars A and B.
The surface temperature of star A is known to be 
.
Determine the surface temperature of star B.
Star B appears less bright than star A when viewed from the Earth. Use the figure above to suggest, with a reason, how else the physical appearance of star B compares with that of star A.
is the peak wavelength, 
is the thermodynamic temperature of the body and 
is Wien's constant.
.
