Experimental

Building a Single Pendulum

Your first goal is to build and test a single pendulum. From the materials provided, choose a pendulum mass and string. You may also use any other masses and strings you want BUT you cannot do something that may damage school property or harm yourself or your classmates. Carefully hang the string from an object of appropriate height such that the pendulum will not bump into anything as it swings. You can use ring stands/bars as needed to move the pendulum away from any furniture.

Deliverable 12: Describe the properties you choose for your pendulum and submit a photo of your set-up.

Stabilize your phone or camera so that it does not move when you record the videos. Record a video of your pendulum at four different (but known) angles. Try a range of both small angles and large angles. Make sure the pendulum stays in frame at all times and you are recording until the pendulum stops moving. Also, make sure you are confining the motion of your pendulum to only 2 dimensions (i.e. the pendulum should not move towards or away from the camera, just side to side).

Import your videos into Logger Pro or Capstone and track the motion of the pendulum mass. You may find it useful to add a small piece of painters tape or other marker to the pendulum for easy tracking. For each video, export the positions found via the manual object tracking. 

Once you have the positions of from the manual object tracking, convert these into angle as a function of time for use in the data analysis section.

Deliverable 13: Submit the code you use to convert the positions to pendulum angles.

Building a Double Pendulum

Now we are going to build a double pendulum.  From the materials provided, choose two pendulum masses and string. You may also use any other masses and strings you want BUT you cannot do something that may damage school property or harm yourself or your classmates. Carefully hang the string from an object of appropriate height such that the pendulum will not bump into anything as it swings. You can use ring stands/bars as needed to move the pendulum away from any furniture.

Deliverable 14: Describe the properties you choose for your pendulum and submit a photo of your set-up.

Choose a small angle and a large angle. Record the pendulum swinging four times: once when the top and bottom angles are small, once when the top is large and the bottom is small, once when the top is small and the bottom is big, and finally when both angles are large. 

Import your videos into Logger Pro or Capstone and track the motion of the pendulum masses. You may find it useful to add a small piece of painters tape or other marker to the pendulums for easy tracking. For each video, export the positions found via the manual object tracking. 

Once you have the positions of from the manual object tracking, convert these into angles as a function of time for use in the data analysis section.

Deliverable 15: Submit the code you use to convert the positions to pendulum angles.

Deliverable 16: Discuss two ways in which your experimental pendulum is different from the simulated pendulum. One reason should be a consequence of how the pendulum was built and the other reason should be an assumption made in the theory. Discuss how these differences may affect the comparisons.