Galileo's Experiment - Diluted Gravity

Purpose: Demonstrate that the acceleration due to gravity is the same for light & heavy objects.

1.)    Set up a ramp using a 4 foot (1.22 m) metal channel on a book or two.

2.)    Measure the angle of the ramp & the height of the high end off the table.

To measure the angle, do the following: Measure the length of the ramp. Put the following in your calculator (in degree mode):

sin^-1(height/length). This will be a pretty good approximation of the angle of the ramp.

3.)    Time a ball rolling from one end of the ramp to the other at least 6 times. Toss out the high & low times. Average the times.  Calculate the acceleration as d = 1/2 a t². The value of "d" is the vertical height, "t" is the average time.

4.)    Repeat step 3 with a lighter or heavier ball.

Do this for 3 different angles.

5.    a) Plot a curve (1) of acceleration vs. angle for glass & steel balls.

        b.) Plot a curve (2) of d vs. t² for glass & steel balls.

        c.) Plot the curves from 5a on the same axes. Plot the curves from 5b on the same axes. How close are they? Did you expect them to be close? If they are not what could you have done to improve the graphs? Did acceleration increase with angle? What could have thrown your results off?

Sample table: