2.  Point at which all other points on the object rotate around  During motion the CM will move in the same path that a simple particle would move if subjected by the same force  Objects supported at their center of mass will remain balanced

5.  Centre Of Gravity - YouTube Centre Of Gravity - YouTube

6.  In order to make an object start rotating about an axis, a force is required  However, not only the amount of force applied but also the position from the axis to which it is applied is important in determining the amount of rotation (angular acceleration  Distance from axis is called the Lever Arm

7. A longer lever arm is very helpful in rotating objects. © 2014 Pearson Education, Inc.

8.  Combination of amount of force and distance from axis is called Torque (τ)  A torque is necessary in order to provide angular acceleration  τ = rF r- dist from axis  Units - N m  In order to use this equation, the force must be perpendicular to the axis of rotation

9.  A biceps muscle exerts a vertical force on the lower arm as shown. Calculate the torque acting on the lower arm if the muscle is attached 5.0 cm from the elbow.

10.  A wrench is pulled by a force of 30 N at an angle of 30° with the axis and a distance of 15cm from its pivot end. What torque is acting on it?

11.  Two forces (F B = 20N and F A = 30N) are applied to a meterstick which can rotate about its left end. F B is applied perpendicular at the midpoint. F A is exerted at the endpoint at an angle of 30 o. Which exerts the greater force?