Consider an electric kitchen stove (surface area A=0.06 m^2) made of a metallic
ID: 1443156 • Letter: C
Question
Consider an electric kitchen stove (surface area A=0.06 m^2) made of a metallic plate that reaches a temperature of 200 degrees Celcius when it is turned on. Assume the plate's emissivity is e=0.9. (Stefan-Boltzmann constant =5.67×108 J/(s m2 K4); Wien's constant b=2988 m K).
a) Calculate the net radiative heat transfer rate if the kitchen’s temperature is 20C. Include the sign in your answer.
b) What is the wavelength (in m) of the radiation emitted by the stove of part a)? Express your answer with 3 significant figures.
Explanation / Answer
a) Q= e A (T1^4 -T2^4)
T1 =200+273 = 473C
T2 = 20+273 = 293C
= .9*5.67*10^-8 * 0.06 *( 473^4 - 293^4)
= +130.69 J
b ) lamda = b/T
= (2988*10^-6)/ 473 = 6.317 m