Video narration
Why is a fan's motion different from moving in a straight line? Look at the fan. Every point on a blade moves around a fixed center-the axis-tracing a circle. That is rotational motion. When the blade completes one full turn, that angular displacement is one rotation. The rate its angle changes is angular velocity: how fast the fan turns. The key part: every point on the same blade shares the same angular velocity, but not the same distance traveled. A point near the axis follows a small circle. The tip follows a larger one, so in the same time it covers more distance and has greater linear speed. When a force acts at a distance from the axis, it can create torque-the turning effect that produces rotation. So why isn't the fan moving straight? Its points turn around an axis in circles. That's rotational motion.