Acceleration and Force in Uniform Circular Motion

Abstract

Uniform circular motion (an object moving at a constant speed along a circular path) is a simple but important example of non-linear motion. In this activity, students first make qualitative experimental observations about the force needed to produce this kind of motion. Students are next presented with a Model that shows the velocity vectors at two points during uniform circular motion and are guided through the process of calculating the magnitude and direction of the average acceleration for a specified angle. Student groups report results for different angles and the pattern generated as the angle decreases allows them to discover the concept of instantaneous acceleration. A theoretical derivation of the formula for instantaneous acceleration is presented, after which students verify that the theory confirms their calculations about acceleration and preliminary observations about force.

Level: High School
Setting: Laboratory
Activity Type: Learning Cycle

Discipline: Physics
Course: Physics (algebra-based)
Keywords: uniform circular motion; centripetal force