2. 8-4 Torque The cause of circular motion is often torque. Torque is the product of the component of force perpendicular to the lever arm or moment arm. The rotational analog of Newton’s second law (F=ma) is t = I a. t = torque Always only use the perpendicular component of force to multiply by the lever arm.

3. 8-5/8-6 Rotational Dynamics; Torque and Rotational Dynamics F=ma=mr a …. So t =mr 2 a …(for a point mass) Newton’s second law in rotation land is St = I a See Example 8-11 See Chart p 223 See Example 8-12

4. Homework Page 235 29-32 and 34-35,37