### Simple Harmonic Motion (MBL) Pre-lab Assignment

The final experiment of the semester is " Simple Harmonic Motion - MBL". Make sure you look over the write-up for that experiment in the manual, and not the write-up for the "Harmonic Motion and Energy" experiment.

The Simple Harmonic Motion experiment is very qualitative, but there are some measurements to be made. One of these is to find the period of oscillation of the pendulum. Use the simulation to measure the oscillation period for a simple pendulum (a mass on a string) for three different lengths of the pendulum.

 Length Period (s) 8 cm 12 cm 16 cm _______ _______ _______

The pendulum you will use in the experiment is not a simple pendulum. In the first part of the experiment you will use a mass M mounted on a rod of mass m. The rotation occurs about the center of the rod, and the position of the mass M is adjustable.

In the experiment you will position the mass M on the rod 8, 12, and 16 cm from the rotation point and measure the period of rotation in each case. How do you expect these periods to compare to those you just measured above for the simple pendulum? Briefly justify your answer.

In step 3 of part III of the experiment (see the write-up in the manual) an equation is given for the position of the center-of-mass of the pendulum. Why does m, the mass of the rod, appear in the denominator but not in the numerator of the equation?