A complete lab that investigates centripetal force.
By Michael Frasier
Abstract: Centripetal force, the force acting on an object moving on a curve, moves toward the center of curvature. It acts in a perpendicular direction to the tangential speed at any given time. This lab explored the effects of increasing centripetal force on the velocity of the curving motion. This was done by spinning a stopper attached to a fishing line in a horizontal circle, working against a variable quantity of hanging weights attached to the other end of the line. It was found that with an increase of centripetal force, the velocity also increases due to the direct relationship between centripetal force and tangential force.
Introduction: This lab will investigate some properties of centripetal force. Centripetal force is the force that acts on an object following a curved path. Centripetal force pulls the object toward the center of curvature so that it won’t go off on a tangent. Centripetal force, combined with tangential force, provide for the curve of the object.
This lab will evaluate the effects of centripetal force by spinning an object around a point, and measuring the force by its velocity. Several trials will gradually increase the weight working against centripetal force and measure the resulting effects on velocity and period of rotation.
I believe that the increase of centripetal force required to negate the increase in gravitational force as an independent variable will necessitate an increase in velocity, which will in turn decrease the revolution’s period.
1. Tie a rubber stopper to one end of a fishing line. Thread the fishing line through a hollow tube. Leave 0.5 m of fishing line between the stopper and tube.
2. Tie a paper clip to the other end of the fishing line.
3. Draw a permanent mark on the fishing line near the bottom of the tube.
4. Measure and record in the data table the weight of one of a set of uniform weights. Make sure you record the weight in newtons. (Use w = mg if necessary.) Slide the weight over the paper clip and bend the clip to prevent the weight from sliding off.