"g" by Strobe Photography
Objective: Determine g using a freely falling object.
Equipment: Strobe light, Camera, golf ball, measuring stick

Method  (data sheet and photo)
1.  Drop the ball with the strobe flashing at 1/30 second intervals and using the "bulb" setting on the camera.  Avoid parallax error by using several meters between the camera and ball.
2.  Analyze the photo for Δd and Δt between 2/30th second intervals as described, then find velocity.

1.  Graph Δv  vs. Δt.
2.  Calculate the slope of the v-t graph showing all work.  What does the slope represent?
3.  Calculate the % error using 9.804  m/s2 as the accepted value for Brockport.
4.  Discuss sources of error in this experiment and describe several ways "g" could be more accurately determined in this experiment.
5.  On your v-t graph, sketch a line that would indicate this lab performed on the moon (g= 1.6 m/s2).

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