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Susan, whose mass is 63 , climbs 63 to the top of the Cape Hatteras lighthouse.

ID: 1698557 • Letter: S

Question

Susan, whose mass is 63 , climbs 63 to the top of the Cape Hatteras lighthouse.
A)During the climb, by how much does her potential energy increase?

B)For a typical efficiency of 25%, what metabolic energy does she require to complete the climb?

c)When exercising, the body must perspire and use other mechanisms to cool itself to avoid potentially dangerous increases on body temperature. If we assume that Susan doesn't perspire or otherwise cool herself and that all of the "lost" energy goes into increasing her body temperature, by how much would her body temperature increase during this climb?

Explanation / Answer

The mass of susan m = 63kg

the height climb h = 63m

(a) The potential energy

          PE = mgh = (63)(63)(9.8)

                         = 38896.2J

(b) If the efficiency is 25%

Therefore the chemical energy

          Q = E/25%

              = 38896.2/0.25 = 155584.8 J

(c) The amount energy lost

          155584.8 - 38896.2 = 116688.6J

the specific heat of human body = 3470 J/kgC

then Q = msT

therefore the increase in temperature

           T = Q/ms = 116688.6 / (63)(3470)

                            = 0.533C