How long does it take a child on a swing to complete one swing if her center of gravity is 4.00 m below the pivot?

Video Transcript

This is College Physics Answers with Shaun Dychko So the child on a swing is like a pendulum and so her period will be two pi times the square root of the length of the swing which is the distance from the pivot to the center of mass of the girl, divided by acceleration due to gravity. So that's two pi times square root of four meters divided by 9.81 meters per second squared, giving a period of 4.01 seconds.