Twiness XuPer.2 01/30/18Circular Motion LabPurpose:to explore circular motion and to analyze the relationship between centripetal force, radius of the path, and tangential velocity.Abstract: tounderstand that the centripetal forcefor an object tocontinue moving in a circle that is at a constantradius, at constant speed. The experiment wascarried out by three parts to understand therelationship among hanging mass, radius of thepath and centripetal force. To calculate thecentripetal force, the weight of revolving mass,hanging mass, radius and time are necessary. Material: revolving mass, hanging mass, string, tube, tape (used as marker), timer.Illustration:FBD(Free Body Diagram):Procedure and Methods:Procedure Part I: Vary the centripetal force while the radius is held constant.
Twiness XuPer.2 01/30/181.Practice with the set-up. Stretch out the string and make sure it moves freely through the tube. Hold the tube in one hand and the end of the string without the stopper in the other. Whirl the stopper above your head and feel the force in the string. How does the force vary as you spin the stopper faster? 2.Measure a radius of about 70 cm. Record the exact radius in your data table (pull the string taut while measuring). Mark the string with tape so that you can keep the radius constant (there must be a constant gap between the tape and the tube). The string must befree to move through the tube.3.Hang a 150 grams on the string.4.Practice whirling the stopper in a circle while keeping the radius constant. Move the tubeas little as possible. Keep the circular path of the stopper as horizontal as possible. The stopper is traveling at the desired speed when the weight on the string provides the necessary centripetal force to maintain the radius. When you can control the apparatus —keeping the radius constant — begin to record data.5.Measure the time it takes to complete 10 revolutions while the stopper is moving with thedesired rotational speed. Divide the time for 10 revolutions, by 10 to get the time for one revolution.6.Add to the mass on the string and repeat the timing of 10 revolutions for two other mass values (250 and 350).