Date Period Name CHAPTER 8 VISUAL 3 TORQUE MAGNITUDE 1. In the human body, the biceps muscle in the upper arm exerts a vertical force on the lower arm, as shown. Torque can be calculated using the magnitude of the force exerted and the distance from the axis of rotation of that force, with the axis of rotation through the joint in the elbow. In Figure a, why can the formula for torque be written as z = Fr instead of r = Fr sin ? 2. Calculate the amount of torque about the axis of rotation through the elbow joint in Figure a. As shown, the muscle is attached 4.8 cm from the elbow, and the force is 600.0 N. Show your work. 3. What is the value of Oin Figure b? 4. In Figure b, is the lever arm longer or shorter than it is in Figure a? Justify your answer. 5. Calculate the amount of torque about the axis of rotation through the elbow joint in Figure b. Show your work. 6. Maria's biceps are attached 4.0 cm from her elbow joint. Stephanie's biceps are attached 5.0 cm from her elbow joint. Assuming that all other factors are equal, which girl will be stronger in many of her arm movements? Justify your answer. Chapter 8 . Rotational Motion