1. Reminder: Bellworks were collected on Friday. Please hand yours in this morning if you haven’t already! Reggie graded and entered those that were turned in Friday.

2. Pendulums

3. A mass (bob) connected to a rod that experiences simple harmonic motion (SHM) as it swings back and forth without friction Frequency (f) – cycles/second (Hz) Period (T) - time for one cycle (sec) Pendulums

4. f = 1/T T = 2π (L/g) ½ L- length of cord g= acceleration due to gravity (at sea level) Does the mass of the bob have an effect on period?

5. A pendulum makes 36 vibrations in 50 seconds. What is its period & frequency?

6. You are building a grandfather clock and want the tick and tock to be separated by one second. How long do you make the cable?

7. Suppose the cable stretches over time. Will the clock run slow or fast?

8. Bellwork What length would you need to change a cord on a pendulum to decrease its period from 1.7 s to 1 s?

9. The length of a simple pendulum is 0.66 m, the pendulum bob has a mass of 310 g. It is released at an angle of 12° to the vertical. With what frequency does it oscillate?

10. What is the bob’s maximum speed?