(e) describe how to determine the position of the center of mass of a plane lamina.
Center of Mass
The center of mass of an object is the point where the average of all the mass of the object is supposed to be concentrated.
Finding Center of Mass of a plane lamina.
Finding the center of mass of a plane lamina is quite easy. Look at the following picture.
To find the center of mass, we will need a plumb line, a clamp stand and a piece of lamina. We will first make a hole anywhere near the edge of the lamina. The lamina will be suspended through the hole in the clamp stand, so that it is hangs and moves freely.
The plumb line would then be suspended from the same point the lamina is hanging. Draw a line on the lamina where the plumb line passes on it. Now we will make another hole at the edge of the lamina, at some distance from the first hole. The process of hanging the lamina, the plumb line and then drawing a line would be repeated.
Now, where the two lines on the paper intersect each other, that point would be the center of mass of the paper.