Direct Measurement: Circular Motion Lab Simulation To be completed in your lab notebook Prelab: 1. Imagine a bug on a record player 10 cm from the center. If the record makes one full rotation, how far has the bug traveled? Explain how you determined your answer. 2. If that bug made one rotation in 0.45 seconds, how fast was it traveling? Explain how you determined your answer. Procedure: 1. Go to: www.Tinyurl.com/CircularMotion1. This simulation is run completely online from a university and is completely safe. 2. Familiarize yourself with the simulation; use this picture as a guide:

3. Create a table in your notebook to compare radius (cm) to Force (N) for nine different trials. 4. Select each of the nine different radii, measure the radius to the center of the brass mass and measure the force applied to the brass weight. Record the measurements in your data table. 5. Go to: www.Tinyurl.com/CircularMotion1B. A similar yet different simulation should open. The tools are very similar but this time you will be changing the speed of the rotation. 6. Create a table in your notebook to compare speed (cm/s) to Force (N) for ten different trials. 7. Determine the distance the brass mass would travel in one rotation and record it in your notebook. 8. Select “Speed #1” from the pull down menu. Click on the stopwatch and move the box that appears so that it can be seen but does not block your view.

9. Time how long it takes the brass mass to make one full rotation. If it is not in the place you would like as the video starts allow the mass to move, hit pause then click “reset” on the stop watch then let it run. Use the time of one rotation and the distance the mass travels in one rotation to calculate the speed in centimeters per second and record it in your data table. 10. Use the force scale to determine the force applied to the brass weight and record it in your data table. 11. Repeat steps #8 - 10 for each of the remaining speeds until your data table is full. Try to be as accurate as possible! Analyzing: Underneath your data tables, write “Analyzing” and you will answer the questions below in complete sentences. Don’t forget to number your answers! 3. Create a graph that takes up at least half a page of the radius to Force from your first lab simulation. Be sure to label all the parts of your graph and follow the guidelines outlined in class for making a good graph. 4. Describe the relationship between the radius of rotation and the force applied for a constant period based on your graph. 5. Create a graph that takes up at least half a page of speed to Force from your second lab simulation. Be sure to label all the parts of your graph and follow the guidelines outlined in class for making a good graph. 6. Describe the relationship between the speed of rotation and the force applied for a constant radius based on your graph. Applying: Underneath your Analyzing questions, write “Applying” and you will answer the questions below in complete sentences. Don’t forget to number your answers! 7. Draw an above the table view of the brass mass on the spinning platform from your lab simulation. Label the velocity vector (assume it is rotating clockwise from that viewpoint) and the force vector. Refer back to the bug on the record player from your pre-lab. 8. If the bug was closer to the center of the record player describe how the distance it traveled in one rotation would change and why. 9. If the bug was closer to the center of the record player as it was traveling the same speed what would happen to the force required to keep it moving in a circle? Explain your answer. 10. If the bug had to remain on the record player while it spins where should it be to minimize the force required to keep it on record player? Explain your answer.