Stefan-BoltzmannÕs Law
(review from Lecture 5)
¥The hotter the object, the more radiation emitted.
¥When the temperature is doubled, the emitted energy increases by a factor of 16!
¥Stefan-BoltzmannÕs Law
¥E= (5.67x10-8 Wm-2K-4 )xT4
–E=2x2x2x2=16
–  4 times     
–(T is temperature in Kelvin)
Sun Temp: 6000K
Earth Temp: 300K
Aguado, Fig. 2-7