1.
A black body is at a temperature of 2880K2880\,\text{K}. The energy of radiation emitted by this object with wavelength between 499nm499\,\text{nm} and 500nm500\,\text{nm} is u1u_1, between 999nm999\,\text{nm} and 1000nm1000\,\text{nm} is u2u_2, and between 1499nm1499\,\text{nm} and 1500nm1500\,\text{nm} is u3u_3. Wien's constant is b=0.28cmKb = 0.28\,\text{cm}\,\text{K}. The correct alternative is