Aerobic workout. After a 5-min workout on a Climb Max stair machine, the readout panel (Fig. P6.99) reports that the 75-kg user burned 19.7 Calories (see Problem 85) and climbed a total of 180 steps.?

(a) If each step is 15 cm in height, how much would the potential energy of the user have changed if she were actually climbing a stairway??

(b) What was her rate of change in potential energy??

(c) At what rate was her metabolism consuming energy??

(d) What is her efficiency in converting the energy in the chemical bonds in her food into potential energy??

(e) She really didn???t change her vertical displacement on this machine, so where did that energy go?

Figure P6.99

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Transcribed Image Text:

500 197 16 Comp Max 10 Clear KIN