Physics Circle home Student Login

Home›Chapters›Heat Transfer and Radiation PYQs›Thermal Radiation: Black Body, Stefan & Wien›Question 35

MHT CET 2026 (15 Apr, Shift 2) · Thermal Radiation: Black Body, Stefan & Wien

Thermal Radiation: Black Body, Stefan & Wien question from MHT CET 2026 (15 Apr, Shift 2)

Q35MHT CET 2026 · 15 APR · SHIFT 2Medium

Thermal Radiation: Black Body, Stefan & Wien

The energy spectrum of a black body exhibits a maximum around a wavelength λ\lambda. The temperature of a black body is now changed such that the energy is maximum at wavelength 2λ/32\lambda/3. The power radiated by the black body will now increase by a factor of

Show answer and solution

Answer: (b)

  1. Wien: T∝1λmT \propto \frac{1}{\lambda_m}, so T′T=32\frac{T'}{T} = \frac{3}{2}.
  2. Stefan: P∝T4⇒P \propto T^4 \Rightarrow factor =(32)4=8116= \left(\frac{3}{2}\right)^4 = \frac{81}{16}
  3. So the answer is (b) 8116\frac{81}{16}.
Report a mistake

More questions on Thermal Radiation: Black Body, Stefan & Wien