1. Rotational Equilibrium and Dynamics
Rotational Dynamics

2. Newton’s Second Law for Rotation
Newton’s Second Law of Motion for Rotating Objects
net torque = moment of inertia * angular acceleration
Τnet = Ια
Positive torque causes counterclockwise rotation
Angular acceleration is counterclockwise
Negative torque causes clockwise rotation
Angular acceleration is clockwise
When net torque is zero, the wheel rotates with constant angular velocity

3. Angular Momentum Rotating objects have angular momentum
The product of a rotating object’s moment of inertia and angular speed about the same axis
Represented by L and measured in kilogram meters2 per second (kgm2/s)
Angular momentum = moment of inertia * angular speed
L = Ιω

4. Angular Momentum
Law of conservation of angular momentum – when the net external torque acting on an object is zero, the angular momentum of the object does not change

5. Rotational Kinetic Energy
Rotational kinetic energy – the energy of an object due to its rotational motion
Measured in joules (J)
Rotational kinetic energy = ½ * moment of inertia * angular speed2
KErot=½Ιω2

6. Rotational Kinetic Energy
Mechanical energy is conserved with rotating objects
Mechanical energy = translational kinetic energy + rotational kinetic energy + gravitational potential energy + elastic potential energy
ME = KEtrans + KErot + PEg + PEelastic
ME = ½mv2 + ½Ιω2 + mgh + ½kx2