Rotational Motion

In this chapter, we first treat the rotation of an extended object about a fixed axis. This is commonly known as pure rotational motion. The analysis is greatly simplified when the object is rigid. To perform this analysis, we first ignore the cause of rotation and describe the rotational motion in terms of angular variables and time. This is known as \(\mathbf{rotational\; kinematics .}\) We then discuss the causes of rotation. This is known as \(\mathbf{rotational\; dynamics ,}\) and concerning it we introduce the concept of \(\mathbf{torque }\) . After that we treat some general cases where the axis of rotation is not fixed in space. In these cases, rigid bodies can undergo both rotational and translational motion, as in the rolling of objects.