Potential and Kinetic Energy of a Pendulum Experiment Worksheet
Fill in the table completely. In the space below the table, show calculations for one of the
Height above 5 cm 15 cm 25 cm
Height of photogate
Height above table,
1. Assuming that air resistance is negligible, would you expect the mechanical energy of the
pendulum bob to be conserved as it swings from position A to position B to position C?
Explain your answer.
2. Express your expectation by filling in the bar chart below for the kinetic energy (KE),
potential energy (PE), and total mechanical energy (TME) at the five positions.
3. In complete sentences, describe what happens to the amount of kinetic energy and the
amount of potential energy as the pendulum bob moves from A to B to C to D to E. Be
clear and specific.
4. If air resistance had a significant influence on the motion of the pendulum bob, then how
would your answers to questions #2, #3, and #4 be different? Explain using complete
Answer each of the following questions in its own paragraph.
5. Based on your data, is the mechanical energy of the pendulum bob conserved? Support your
answer by using actual data from the table.
6. Of the external forces acting upon the bob, which (if any) do work upon the bob? Use a
free-body diagram to help explain your answer. How does this work (or lack thereof) affect
the conservation of mechanical energy?
7. Describe at least two sources of error in this experiment.