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Starter A student records the motion of a spinning object and obtains a theta vs. time graph. The computer gives a fit: q(t) = At2 + Bt + C where A = 6.50 , B = .001 and C = 0.00 What is the experimental value of the angular acceleration a? (1/2)a = 6.50 so a = 13.0 rad/s2 Hint: consider qf = qi + wit + (1/2) at2 Practice Recall from the circular motion study that: qf = qi + wit + (1/2) at2 wf = wi + at You will investigate these relationships. Procedure 1. Connect the smart pulley to the Vernier interface. Connect the interface to the computer. 2. Find the file” Smart Pulley Rotation Lab” on the K drive under Davenport Physics and double click on it. 3. Spin your pulley and once it is spinning hit the green collect button. You will have an angle vs. time graph (q vs. t) and a Angular Velocity vs. time graph (w vs. t ). Analysis A. Obtain a theta vs. time graph. Fit a curve to your graph and sketch the graph. Write down the equation for the fit on the graph. B. Obtain a angular velocity vs. time graph. Fit a curve to your graph and sketch the graph. Write down the equation for the fit on the graph. C. Find the experimental acceleration from your theta vs. time graph. (Twice the coefficient of t2). Call this value E1. D. Find the experimental acceleration from your w vs. time graph (the slope). Call this value E2. E. Find the % difference between your two E1 and E2. Questions Write 1 paragraphs explaining the results ( your two graphs ) including an explanation of: 1. How you obtained the angular acceleration from each graph. 2. How the graphs compare to the y vs. t graph and v vs. t graph for free fall. Lab Report Checklist A. Cover Sheet B. Two Graphs C. Both accelerations and the percent difference. D. Questions E. Summary EXIT A student records the motion of a spinning object and obtains an w vs. time graph. The computer gives a fit: w(t) = At + B where A = 8.50 and B = 1.00 What is the experimental value of the angular acceleration a?