MHT CET202615 April 2026Morning ShiftPhysicsThermal Properties of MatterActual
About black body radiation, which one of the following is a WRONG statement?
Options
- AFor all wavelengths, power radiated is same
- BFor shorter wavelengths, radiated power is more
- Cfor longer wavelengths, radiated power is less
- DAll wavelengths are emitted by the black body
Correct answer
A. For all wavelengths, power radiated is same
Step-by-step solution
According to the spectral distribution of black body radiation (Planck's law), a black body emits radiation of all possible wavelengths, but the energy is not uniformly distributed among them. The spectral emissive power ( E_ ) first increases with an increase in wavelength, reaches a maximum value at a specific wavelength ( _ m ), and then decreases for longer wavelengths. Therefore, the statement "For all wavelengths, power radiated is same" is completely incorrect. Answer: For all wavelengths, power radiated is