MHT CET202615 April 2026Evening ShiftPhysicsThermal Properties of MatterActual
The energy spectrum of a black body exhibits a maximum around a wavelength . The temperature of a black body is now changed such that the energy is maximum at wavelength 2 /3 . The power radiated by the black body will now increase by a factor of
Options
- A256 81
- B81 16
- C162 41
- D16 81
Correct answer
B. 81 16
Step-by-step solution
Using Wien's displacement law, _ m T = b ₁ T₁ = ₂ T₂ T₁ = ( 2 3 ) T₂ T₂ = 3 2 T₁ According to Stefan-Boltzmann law, the power radiated by a black body is P = A T⁴ P T⁴ P₂ P₁ = ( T₂ T₁ )⁴ P₂ P₁ = ( 3 2 )⁴ = 81 16 Answer: 81 16