PLEASE HELP!!! THIS IS MY 4TH TIME POSTING SO PLEASE ONLY ANSWER IF YOU ARE SURE

Question

PLEASE HELP!!! THIS IS MY 4TH TIME POSTING SO PLEASE ONLY ANSWER IF YOU ARE SURE! I really need to get this correct!

THE FIGURE IS JUST A PICTURE OF A GUY RUNNING ACROSS THE CHARCOAL. IT IS NOT NECESSARY TO ANSWER THE QUESTION. A man strides across a bed of glowing embers as seen in the figure below, and due to some very specific physical circumstances, he emerges with no physical harm. Assume the glowing charcoal is covered with a thin layer of ash 0.52 mm thick and is at a temperature of 625°C. The thermal conductivity of ash and charcoal is approximately 1.5 W/(m · K). (Water has a density of 1 g/cm3 and assume the body temperature of 37°C.) The area of the bottom of the man's foot is 300 cm^2.

A) Assume the area of the bottom of each foot comes into only 50% contact with the embers (a rough surface) and the contact lasts 0.10 s for each step. Calculate the heat transferred to only one foot (in three steps).

*Answers I used for part A that were incorrect were: 3.89 kJ, 11.68 kJ, 2.54 kJ and 146.78 kJ

B) Assume he steps onto the fire from slightly wet grass. If his foot is protected by the conversion of water from a liquid to a gas, how much water is needed to carry away the heat from part (a)? (Use the exact values you enter in previous answer(s) to make later calculation(s).)

*Answers I used for part B that were incorrect were: 1.77 g, 5.31 g, 1 g, and 58.16 g

C) How thick would this layer of water on the sole of each foot need to be? (Recall that the area of the bottom of each foot comes into only 50% contact with the embers.)

*Answers I used for part C that were incorrect were: .118mm, .354mm, .0667 mm, and 3.88 mm

THANK YOU!

Explanation / Answer

A) the heat transferred = (1.5 * 300)/45.67

                                      = 9.85 kJ

B)   water is needed to carry = (34 * 5.67 * 89)/(34 * 5.322)

                                               = 17.83 gm

C)   thick would this layer of water = (5 * 7.83 * 21)/10000

                                                      = 0.082 mm

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