Experiment 5B: Friction MIT 8.01T Physics IGoal To investigate the friction of a string wrapped around a cylinder, observe that it increases exponentially, and to measure the friction coefficient µ. (A theoretical expression is derived in the appendix to the write up for the experiment.)Starting DataStudio: Create a new experiment. Plug a force sensor into the 750 and drag it to the input in the Setup window. Double-click the Force Sensor icon.Force Sensor: Set it for 10 samples/s and low sensitivity. ClickSampling Options: No boxes checked. No delayed start. Stop after 10 s.Set Up : Choose large or small cylinder. Both kinds at each table. 100 gm brass weight + 5 gm holder = 1.03 N. Small Cylinder Large CylinderMeasuring technique: Tare the force sensor. Ensure string passes over pulley before all measurements. Do not wrap the string over itself. Wrap string 2 ¼ turns around cylinder. Increase ccw torque on cylinder smoothly to the slipping point, then turn slowly for 1 or 2 seconds. Practice this, so you get 1 or 2 peaks of the force in 10 s, then record the force with DataStudio.Measuring the Friction: Choose the largest magnitude of Force as the friction. Use the Smart Tool or the Statistics (Σ) Tool.Recording the Friction: Measure the friction for the string wrapped ¼, 1¼, 2¼, 3¼ and 4¼ turns. Express these in radians and type them as the independent variable, along with the friction force as the dependent variable, into a table in DataStudio. Include the force of 1.03 N when the wrap angle is 0 as an entry in your table. Plot the table on a graph and carry out a User-Defined Fit with the function 1.03*exp(-C*x).Fit Result (large cylinder):Fit Result (small
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