please help, what is part C and D thanks! If each city block maintains the same

Question

please help, what is part C and D thanks!

If each city block maintains the same radiated power for 1.6 h and there are no other energy losses, what is the final temperature of the cube of air above the block in city 1? The density of air at 30.0 C is 1.16 kg/m3.

Problem 16.81 Suppose city 1 leaves an entire block (100 m x 100 m) as a park with trees and grass (emissivity 0.96) while city 2 paves the same area over with asphalt (emissivity 1.0). Sunlight heats each surface to 42.0 GC by sunset, and then the surface radiates its heat into a cube of air 100 m on a side and at 30.0 oC. Part A At What rate does the park in city 1 deliver energy to the air at sunset? Express your answer to three significant figures and include appropriate units. 772 kW Submit My Answers Give Up Correct Part B At what rate does the asphalt in city 2 deliver energy to the air at sunset? Express your answer to three significant figures and include appropriate units. 804 kW Submit My Answers Give Up Correct

Explanation / Answer

Part A )

rate of the energy is delivered is = e A ( T4 - To4 )

= 0.96 X 5.67 X 10-8 X 1002 X ( 3154 - 3034 )

= 771142.57 W

= 772 kW

Part B )

rate of the energy is delivered is = e A ( T4 - To4 )

= 1 X 5.67 X 10-8 X 1002 X ( 3154 - 3034 )

= 803273.51 W

= 804 kW

Part C )

772 X 103 X 1.6 X 3600 = 1003 X 1.16 X 1008 X ( T - 30 )

T - 30 = 3.80

T = 33.8oC

Part D )

804 X 103 X 1.6 X 3600 = 1003 X 1.16 X 1008 X ( T - 30 )

T - 30 = 3.96

T = 33.96oC

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