#### What is center of gravity and why is it important? How can we find the location of the center of gravity of different objects?

The center of gravity of an irregular flat sheet is given by the intersection of plumb lines from two suspension points.

## Center of Gravity

CENTER OF GRAVITY, the point at which the gravitational attraction of a body may be considered to be concentrated. Since gravitational attraction depends on mass, the mass of the body may also be considered to be concentrated at this point. For this reason, the center of gravity is also known as the center of mass.

The fact that alli the mass and weight of a body may be taken to be acting at a single point greatly simplifles many calculations. For example, the motion of a spinning baton thrown into the air appears to be rather complex. Actually, while the baton rotates about its center of gravity, the center of gravity itself moves through a simple arc.

The center of gravity of a body may or may not be a point on or within the body. For bodies of regular geometrical shape and uniform denSity, it is at their geometrical center. Thus, the center of gravity of an automobile tire or a hollow cube would not be a point on the tire or cube, while the center of gravity of a solid cube would be located at a point of the cube.

When an object is suspended, the center of gravity always lies directly below the point of suspension. This fact can be used to find the center of gravity of an irregularly shaped flat object. If the object is suspended successively from two points and lines are drawn on the object indicating the positions of plumb lines hung from the points of suspension, the two lines will intersect at the center of gravity. A third point of suspension will provide a third line also going through this point as a check.