Define: a. Rigid body b. Rotation motion 2. Define and write expression for: a. Density b. Torque c. Moment of inertia 3. State the Principle of rotational dynamics relating the torque and angular acceleration. 4. Define and write expression for Angular momentum

Here's the answer to question 3:

The Principle of rotational dynamics states that the net torque acting on a rigid body is directly proportional to its angular acceleration, with the constant of proportionality being the body's moment of inertia.

Mathematically, this is expressed as:

$$\tau_{\text{net}} = I \alpha$$

where:
$\tau_{\text{net}}$ is the net torque acting on the body.
$I$ is the moment of inertia of the body.
$\alpha$ is the angular acceleration of the body.