Concept explainers
Championship swimmers take about 22 s and about 30 arm strokes to move through the water in a 50 m freestyle race.
a. From Table 11.4, a swimmer’s
b. If half the energy is used in arm motion and half in leg motion, what is the energy expenditure per arm stroke?
c. Model the swimmer’s hand as a paddle. During one arm stroke, the paddle moves halfway around a 90-cm-radius circle. If all the swimmer’s forward propulsion during an arm stroke comes from the hand pushing on the water and none from the arm (somewhat of an oversimplification), what is the average force of the hand on the water?
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