(Solved): The Achilles tendon transfers force generated in the two heads of the calf muscle to the back of yo ...

The Achilles tendon transfers force generated in the two heads of the calf muscle to the back of your heel, as shown in the image. Thus, when you contract your calf, it pulls on the back of your heel via the Achilles tendon, pointing your toe. The simplest model for the Achilles tendon is a simple bundle of inextensible fibers - a rope that doesn't stretch. The foot we model as a rigid body that rotates around the ankle joint. In this problem we explore the forces generated in the Achilles by standing and jumping. a) Do you the origins of the phrase "Achilles heel" and how it is used? (If not, look it upl) b) If you balance on the toes of one foot at the edge a step (shown in blue in the diagram), your ankle is in equilibrium (not moving). This means that the forces sum to zero (here, they are all in the vertical direction), as do the Turn-in 6.docx torques around your ankle. For the foot dimensions shown in the image and a mass for the person of \( 70 \mathrm{~kg} \), find the tension in the Achilles tendon. Assume that the bottom of the foot is perfectly horizontal, so that in the diagram the angle between the foot and the Achilles is \( 90^{\circ} \). c) Find the tension in your Achilles if you stand on tiptoe (still on one foot) so that the angle \( \theta \) between your foot and the stair is \( 30^{\circ} \).