Rotational Dynamics Virtual Lab All Questions and Calculations (3 Points) Part IA Torque 1. What eventually happens to the Lady Bug? 2. According to Newton's Second Law, what does a net force do? 3. According to Newton's Second Law for Rotation, what does a net torque do? 4. For this simulation what would be causing the centripetal force? 5. Why does the Lady Bug eventually go ying off the disk? Part IB 1. How does the acceleration vector change over time (include both magnitude and direction)? 2. Will the acceleration vector ever point directly to the center? Why or why not? Part IC 1. Describe the motion of the wheel. 2. What happened to the acceleration vector? Why does this happen? 3. What is the net torque (black line on the torque graph) Part ID 1. Right after you set the break force record the net torque. 2. Eventually the disc comes to a stop and the net torque becomes zero. What happens to the brake torque? Why? 3. How is the Torque in rotational motion like Force in linear motion? Rotational Dynamics Virtual Lab Procedure Part I Torque 1. G0 to htt :l/ het.colorado.edu/simulations/sims. h ?sim=T0r ue 2. Launch the simulation by clicking on the center of the image. Torque 3. This simulation runs at a remote site so you should not have to download any software. Be aware it may react slowly depending on your internet connection. 4. Click the tab at the top that says torque for Part IA. 5. Set the force equal to 1 N. WM 6. Click Go let this run for at least 10 seconds. Time is determined by the distance the graphs have gone. Observe the Lady Bug on the Wheel and note the time when it falls off. Record the Torque. Answer the questions concerning this section of the lab. 0. Click on Reset All to reset the simulation for Part [3. ~H nasal AI 11. Click Go to start the simulation. 12. Observe the acceleration vector (Shown in Red) 13. Answer the Questions for Part [3. 14. Reset the simulation for Part IC. 15. Start the simulation 16. Let the simulation run for 2.5 s and then click Stop. 17. Now set the brake force to 1.00N Part II Moment of Inertia 1. Calculate Moment of Inertia (Please show calculations) 2. Radius 3. Calculate applied force (Please show calculations). 4. Calculate the angular acceleration (Please show calculations) 5. Convert to degreesls2 (Please show calculations) 6. Calculated moment of inertia for thin ring. 7. Actual moment of inertia for thin ring. 8. Explain why there is a difference between your calculated value and the actual value for the moment of inertia. 9. Even when the force on the platform changes, the moment of inertia graph remains constant. Why? 10. What is the relationship between the mass of the disk and the moment of inertia? 11. What is the relationship between the radius of the disk and the moment of inertia? 12. How is the Moment of Inertia in rotational motion like mass in linear motion? Part III Angular Momentum 1. What is symbol and SI unit for angular momentum? 2. Calculate the angular moment of the solid disk (Please show your calculations) 3. While the disk is moving, change the inner radius to 2. 4. Changing the inner radius automatically changes the angular velocity to 36 degrees/s. Why (mention moment of inertia and angular momentum in your answer)? 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. Hold down the left mouse button. Move your mouse to apply a force. Try to apply a torque of lONm. Click on the ruler check box to show the ruler. III-urE-ZC- Record the radius of the point between the green and pink areas. Be sure to record the value in meters, not in centimeters. Calculate the applied force using r=Fr. Calculate the angular acceleration of the disk using r=Ia. Use the moment of inertia calculated earlier. Convert the value from above from rad/s to degrees/s. Show your calculations. Compare to the value found in the Angular Acceleration Graph. Predict what will happen to the moment of inertia if you keep the mass of the platform the same, but you create a hole in the middle (increase the inner radius). Set the inner radius equal to 3.99. Calculate the moment of inertia for this shape using the equation for a thin disk I=MR . Set the disk in motion and check your answer by looking at the moment of inertia graph. Complete the Questions for Part 11. Part III 1. T-'P'S"F Click the Angular Momentum tab at the top. Set the scale of the moment of inertia and angular momentum graphs to show a range of 2 to -2. Set the Angular Velocity to 45 degrees/s. Calculate the angular momentum using L=Im. While the disk is moving, change the inner radius to 2. Observe the graphs. Answer the questions for Part 1]]. Conclusion Write a conclusion using the criteria given to you by your teacher. 5. How are Angular Momentum and Linear Momentum similar and how are they different? Conclusion (10 Points) Fume-mammal 1.00 ll ' 18. Click Go to start the simulation again and run until 5 .0s. Observe. 19. Answer the questions for Part IC. 20. Reset the simulation for Part ID. 21. Let the simulation run for 2.53. 22. Stop the simulation and set the Force of the Brake to 3.00N. Restart the simulation and let it run to 5.03. 23. Observe the changes in the net torque. 24. Answer the questions for Part ID. Part II Moment of Inertia 25. Click on the Moment of Inertia Tab. 26. To best see the graphs, set the scale of the Torque graph to show a range of 20 to -20. This is done by clicking on the top negative button found on the right side of the graph. [33 a 27. Set the Moment of Inertia Graph to show a range of 2 kgm2 to -2 kgm2 28. Set the Angular Acceleration graph to show 1,000 degrees/s2 to -1000 degrees/s2 29. Calculate the moment of Inertia for the disk with the information given under the disk image. Rmrnuu' I E Hunt mm " mmm| Imhu ' Fumeufnm| amh ' This is a solid disk rotating around its center. 30. Hold the mouse over the disk so the mouse nger is pointing anywhere between the green and pink circles. G