Problem 11.46 Part A- A 68 kg hiker walks at 5.0 km/h up a 3% slope. The indicat

Question

Problem 11.46 Part A- A 68 kg hiker walks at 5.0 km/h up a 3% slope. The indicated incline is the ratio of the vertical distance and the horizontal distance expressed as percentage What is the necessary metabolic power? Hint: You can model her power needs as the sum of the 380 W power to walk on level ground plus the power needed to raise her body by the appropriate amount. Assume that the efficiency of the body in using energy is 25%. Express your answer to two significant figures and include the appropriate units. PValue Units Submit My Answers Give Up Provide Feedback Continue

Explanation / Answer

tan(theta) = 0.03

theta = 1.72 deg

F = m g sin(theta) = 68 x 9.8 x sin1.72

F = 20 N

v = 5 x 1000 m / 3600s = 1.39 m/s

P = F v = 28 W ........Ans

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