A tungsten filament lamp behaves nearly like a blackbody
PHYSICS · Multi-part · AP · Physics 2: Algebra-based · Modern Physics · Modern Physics
Problem
A tungsten filament lamp behaves nearly like a blackbody. Initially the filament operates at 2400K and has its peak intensity at wavelength λ0.
The supply voltage is then adjusted so that the new peak wavelength becomes 54 of the original value.
(i) Determine the factor by which the absolute temperature of the filament changes.
(ii) Calculate the new operating temperature of the filament.
(iii) By what factor will the total power radiated per unit area of the filament change after the adjustment? (Neglect any change in emissivity.)