1. The problem asks: What is circular motion? 2. Circular motion is the movement of an object along the circumference of a circle or rotation along a circular path. 3. The key formula for circular motion is the centripetal acceleration: $$a_c = \frac{v^2}{r}$$ where $v$ is the speed of the object and $r$ is the radius of the circle. 4. Important rules: - The velocity vector is always tangent to the circle. - The acceleration vector points towards the center of the circle (centripetal acceleration). - The speed may be constant, but the velocity changes direction continuously. 5. Circular motion can be uniform (constant speed) or non-uniform (changing speed). 6. In uniform circular motion, the centripetal force $F_c$ required to keep the object moving in a circle is: $$F_c = m a_c = m \frac{v^2}{r}$$ where $m$ is the mass of the object. 7. This force acts towards the center of the circle, keeping the object in circular motion. Final answer: Circular motion is the motion of an object along a circular path, characterized by centripetal acceleration directed towards the center of the circle, given by $$a_c = \frac{v^2}{r}$$.