Center of Mass

To locate the center of mass of different objects. Materials Cardboard, string, scissors, scotch tape. Procedure 1. Cut an irregular shape out of cardboard for your object. 2. Tape a piece of string anywhere along the edge and hang the object freely on a vertical surface. a. Draw a straight line across the object along the line defined by the string, using a straightedge. b. Tape the string to another part of the edge and repeat 2.a. c. Repeat 2.b. The intersection point of the three lines is the center of mass of the object. 3. Make a tiny hole at the center of mas. Pass a string through the hole and tape the end of the string to the other side of the cardboard. Suspend the object by the string. The object should hang nicely balanced because no net torque exists. Questions 1. Cut the letter C out of cardboard and locate the center of mass. Is it within the frame of the letter? Can it be balanced at the center of mass as in 3? 2. Fashion a cardboard silhouette in the shape of the continental USA (exclude Alaska and Hawaii) and estimate the position of its center of mass. 3. The center of mass for a human is in the abdomen just below the navel. We can maintain a stable standing posture as long as the center of mass is directly above our feet. Explain in terms of the location of the center of mass, the physical reason why you begin to fall forward when you lean forward far enough.