Solve the following problems:
Forces Exerted by Achilles Tendon Applied to Bicycle
Q1. A bicycle wheel has a diameter of 63.9 cm and a mass of 1.87 kg. Assume that the wheel is a hoop with all of the mass concentrated on the outside radius. The bicycle is placed on a stationary stand and a resistive force of 121 N is applied tangent to the rim of the tire.
(a) What force must be applied by a chain passing over a 9.10 cm diameter sprocket if the wheel is to attain an acceleration of 4.48 rad/s2?
Your response differs from the correct answer by 10% to 100%. N
(b) What force is required if the chain shifts to a 5.56 cm diameter sprocket?
Q2. When a person stands on tiptoe (a strenuous position), the position of the foot is as shown in Figure P8.16a. The total gravitational force on the body, Fg, 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 P8.16b, 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 θ when Fg = 830 N.