Question

please answer it correctly as I posted it before and it's wrong.

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 20 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 Express your answer with the appropriate units. UA ? D = Value Units Submit Request Answer Part B What is this force as a fraction of the runner's weight? Express your answer numerically. VO AKO ? = w Submit Request Answer

Answer 1

that of the person, Given mass n = 60 kg runner The speed of the 5 km 20 noin 6x103 4.16 m/s 20 X 60 force, Drag P = Der = 1.225 kg where m3 We have the equation of fo - Pric A Density of fluid (air) V= speed of the moving body moving body = 4.16 m/s Drug Coefficient. It depends upon Shape and friction of the object. Drag Coefficient for an adult in Upright position is 1.2 (approu ingeite) - man a: C 1.2 A is the 0.72 m² area of Cooss section → 1,225 X F. *(4.16)x. 1.2 x 0.72 x 2 9.15N

a So Drag the force of runner during Желсе, fp = 9.15 Newton also called D => is -> D=9.15 N b) as fraction of runner's Darag force weight, a D W mag acceleration due to m= 60kg, ga 9 gravity = 9.8m/5 1) 9.15 0.0155 = 60X9.8 Als 0.0155