Shortcut Methods
Shortcut Methods and Tricks to Solve Numerical Problems on Rotational Motion About a Fixed Axis
I. Kinematics
1. Uniform Circular Motion: To find the tangential velocity (v) of a point on the rim of a rotating disk, simply multiply the angular velocity (\omega) by the radius (r) of the disk.
2. Uniform Angular Acceleration: To find the angular displacement (\theta) of a rotating wheel that starts from rest and accelerates uniformly, use the following formula:
II. Dynamics
1. Rotational Kinetic Energy: To calculate the kinetic energy (K ) of a rotating disk or wheel, utilize the formula:
2. Angular Momentum: Determine the angular momentum (L ) of a rotating wheel, pulley, or other objects employing the equation:
3. Tension in a String: For a rotating pulley with a mass attached to a string, apply the equation