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KIei asked in Science & MathematicsPhysics · 5 years ago

Physics treadmill question. PLEASE HELP! Been trying for hours explain all parts please I will give best answer.?

Running on a treadmill is slightly easier than running outside because there is no drag force to work against. Suppose a 60 kg runner completes a 5.0 km race in 18 minutes.

Part A

Determine the drag force on the runner during the race. Suppose that the cross section area of the runner is 0.72 m2 and the density of air is 1.2 kg/m3.

Part B

What is this force as a fraction of the runner's weight?

2 Answers

Relevance
  • oubaas
    Lv 7
    5 years ago

    average speed = 5000/(18*60) = 4.630 m/sec

    drag force = V^2/1.6*A = 4.63^2/1.6*0.72 = 9.65 N

    (drag force/runner weight) in % = 100*9.65/(60*9.8) = 1.64 %

  • ambuj
    Lv 4
    5 years ago

    Fd = ρν²ACd/2.

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