At high noon, the Sun delivers 1 000 W to each square meter of a blacktop road. If the hot

asphalt transfers energy only by radiation, what is its steady-state temperature?

1 answer

Stefan’s Law: P = σAeT4

σ = 5.669 x 10-8 W/m2K4

(e = 1 for blacktop)


Pin = Pout

σAineT4 = σ Aout e T4

(1000) = 5.669 x 10-8 1*1* T4

T = 364 K