# 9: Rotational Kinematics, Angular Momentum, and Energy

- 9.10: Conservation of Energy
- Energy is conserved in rotational motion just as in translational motion.

- 9.1: Quantities of Rotational Kinematics
- The angle of rotation is a measurement of the amount (the angle) that a figure is rotated about a fixed point— often the center of a circle.

- 9.2: Angular Acceleration
- Constant angular acceleration describes the relationships among angular velocity, angle of rotation, and time.

- 9.3: Rotational Kinematics
- The motion of rolling without slipping can be broken down into rotational and translational motion.

- 9.4: Dynamics
- Rotational inertia is the tendency of a rotating object to remain rotating unless a torque is applied to it.

- 9.5: Rotational Kinetic Energy
- The rotational kinetic energy is the kinetic energy due to the rotation of an object and is part of its total kinetic energy.

- 9.6: Conservation of Angular Momentum
- The law of conservation of angular momentum states that when no external torque acts on an object, no change of angular momentum will occur.

- 9.7: Vector Nature of Rotational Kinematics
- The direction of angular quantities, such as angular velocity and angular momentum, is determined by using the right hand rule.

- 9.8: Problem Solving
- Identify the problem and solve the appropriate equation or equations for the quantity to be determined.

- 9.9: Linear and Rotational Quantities
- The description of motion could be sometimes easier with angular quantities such as angular velocity, rotational inertia, torque, etc.