Introduction:
In this lab you will investigate the motion of an object undergoing a centripetal acceleration caused by a centripetal force. We will use the apparatus pictured below. The following terms will be used to refer to the apparatus: (A) crossarm, (B) counterbalance, (C) mass, (D) indicator rod, (E) pulley, (F) vertical shaft, and (G) spring. The mass (C) will rotate in a horizontal circle about the vertical shaft, or axis (F). The spring (G) will hold it in so that the string attached to the mass remains vertical. We will explore the relationship between the force exerted by the spring and the speed at which we rotate the mass. Notice that all the forces on mass C are gravity, vertical tension and horizontal tension from the spring G. If we run the experiment so that the spring is perpendicular to the vertical string, then the force making the mass C move in a circle is only the force due to spring G.
