Chapter 8, Problem 72A

To determine

To explain: The reason for theappearance of gymnast to be floating on air.

Explanation of Solution

Introduction:

Center of mass of an object is defined as the point at which the sum of weighted relative position of the distributed mass is zero. If the force is applied at this point, then only linear acceleration will be present. It is the mean location of a distribution of mass in space.

When gymnasts take a leap, her one leg is in forward direction that is leading and other leg is backward direction that is trailing. Her legs are parallel to earth so it has some mass parallel to earth. During leap, when she raises her arm above head, center of mass will also shiftabove. Also due to jump, center of mass is shifted above the head due to which gymnast looks like floating in air.