Question

When a person stands on tiptoe (a strenuous position), the position of the foot is as shown in Figure a. The total gravitational force on the body, Fe, is supported by the force n exerted by the floor on the toes of one foot. A mechanical model of the situation is shown in Figure b, where T is the force exerted by the Achilles tendon on the foot and R is the force exerted by the tibia on the foot. Find the values of T, R, and when F = n = 800 N. (For O, enter the smaller of the two possible values between 0° and 90°.) -Achilles tendon Tibia IR 15.0° 18.0 cm 9601 25.0 cm z z o

Answer 1

sreebody diagram: Rx = Rsinus) Ry - RCLE) In 800 & Fx-o R sincis) - Tsino o R- Tsing/sincis) & Fy a 800N - ROB (15) + Tcoso o 40-0 -(800) [(18cm) cso] ++ [125cm - 18em)] -o =52057.142 NJ colo R = 2054.142 Isin o cose Sincis) 2057.142 sine cose - (2057.142) Coso = 800 Tou (15) which sino.coso - (Toulis) cost o. lova Sinve a lacosro [Ian (15) to caso + [ 2tau 115) (014)-1] con + Coulong o. let u cose 2. U -0944

by using quedoratic cacation U2 0.871 ae -0.016 or cat [ 10=87;)] o cos 6.06 ) - 93.cits simposible T = 2057.142 Cos (27) = 1920.50 N R = 1920.50 sin (21) Sin (15) R = 2659 176 N