How well do you understand the physical pendulum?

posted Mar 30, 2018, 9:23 AM by Barbara Fortunato   [ updated Apr 11, 2018, 4:41 PM ]
2: M 4/9 lab, 4: T 4/10 lab

Today, we'll design an experiment to find the moment of inertia about the center of mass of an odd shaped object.  In order to do this, you'll have to understand the motion of a physical pendulum.  Once you finish taking data, you'll finish your brief individual write-up of this lab.  Do your write-up on paper which you can turn in in hard copy.  Your analysis should include a labeled sketch of the set-up, at least one free body diagram, sentences about what you did and why, and calculations necessary to find the moment of inertia about the center of mass.  YOU MUST DO AT LEAST TWO DIFFERENT TRIALS to verify your calculation of the moment of inertia ABOUT THE CENTER OF MASS.

With any time remaining, you can finish any required problems from topics up to this point, or if you've already completed all required problems, you can watch the homework video. 
Homework:  Test on velocity dependent forces, gravitation/orbits, and simple harmonic motion on Thursday, April 12th.  Finish your lab write-up, which is due Thursday, April 12th, same day as the test.  The test includes this material, so it's important that you understand the lab.  Watch the following two videos - they're the same problem with two different methods which are both useful: 
  • Method 1:  small mass dm, constant applied force, finite distance y
  • Method 2:  whole mass remaining, changing applied force, force constant for very small distance dx

Heavy Rope

Heavy Rope 2