"g" by Pendulum
Measure "g" using the period (T) of a pendulum.
Equipment:  pendulum, pressure clamps, meter stick, stopwatch, vernier caliper

1.  Sketch and label the set up.
2.  Determine the length (L) of the pendulum to the center of the ball (string + 2 diameter of ball).
3.  Swing the pendulum with an arc <10o from the vertical.  Countdown “3-2-1-0” before starting the stopwatch
4.  Record the total time for 50 complete swings.
5.  Repeat for 5 other lengths of the pendulum between 0.2 m and 2 m.

1.  Calculate the period (T) for one swing to the nearest 0.01 second  for each pendulum length, then T2.
2.  Plot the data of L vs T2 (L on the y-axis).  Calculate the slope with units.  What does the slope represent?  Calculate g using your slope and the equation derived in class.
3.  Calculate a percent error using 9.804m/s2 for Brockport.  
4.  Using your graph, predict L by interpolation when T = 1.0s; 2.0s (remember: your x-axis is T2).
5.  Why did we use 50 swings to determine T rather than 1or 2 swings?
6.  How would a 1 second period (T) on earth be different for your pendulum on the moon? (gm = 1.67 m/s2).  
7.  What length pendulum on the moon would produce a 2.0 s clock?
8.  Grandfather clocks have a 2.0 second swing.  If a 3.0 second clock (great grandfather) could be made, how tall would a room have to be?
9.  How would a pendulum bob of different mass affect your results?

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