Circular Motion and Gravitation

This chapter covers motion in circles and the law of universal gravitation.

Key Concepts:

• Centripetal acceleration and force

• Newton’s Law of Universal Gravitation

• Orbits and satellites

Sample Question:

A 0.5 kg object moves in a circle of radius 2 m at 4 m/s. What is the centripetal force?

\[F_c = \frac{mv^2}{r} = \frac{0.5 \times 4^2}{2} = 4\ \text{N}\]