In: Mechanical Engineering
Two materials, one with ε1 = 0.9 and the other with ε2 = 0.2 are available to use as filaments (light sources) for an incandescent lamp. Material 1 can be maintained at 2800 K, whereas material 2 can be maintained at 3000 K. Calculate the rate at which radiant energy is emitted per unit surface area (Watts/m2 ) from each of the two materials in the spectrum 0.4µm < λ< 0.8µm. Which material emits energy at the highest rate in this spectrum (assuming same surface area for both materials)?