Chapter 9.7, Problem 7EYU

Enhance Your Understanding

(Answers given at the end of the chapter)

1. Predict/Explain A piece of sheet metal of mass M is cut into the shape of a right triangle, as shown in Figure 9-24.

Figure 9-24 Enhance Your Understanding 7.

A vertical dashed line is drawn on the sheet at the point where the mass on either side of the line is M/2. The sheet is now placed on a fulcrum just under the dashed line and released from rest. (a) Does the metal sheet remain level, rotate counterclockwise (left end down), or rotate clockwise (right end down)? (b) Choose the best explanation for your prediction from among the following:

1. I.                    Equal mass on either side will keep the metal sheet level.
2. II.                 The metal sheet extends for a greater distance to the left, which shifts the center of mass to the left of the dashed line.
3. III.              The center of mass is to the right of the dashed line because the sheet of metal is thicker there.