Free Fall Apparatus
Free Fall Summary
file:///F:/lab/1/Videos/FreeFall/FreeFallSummary.html
Summary of the Free Fall Experiment
This is a summary of the web-based document on the Free Fall experiment at: http://faraday.physics.utoronto.ca/IYearLab/Intros/FreeFall/FreeFall.html. See that document for the complete discussion. Here we summarise that document in a form suitable for printing.
Equations of Motion
In the absence of air resistance:
where: s = the position at time t s0 = the position at time t = 0 v0 = the speed at time t = 0 g = the acceleration due to gravity. When there is air resistance, it is characterised by a constant :
Then the equation of motion is approximately:
The Apparatus
The precision of the metal scale is one part in 4000. The accuracy of the timer is within its reading error of 0.05 msec. The minimum distance between the suspended object and the Start Gate should be about 10 cm. The minimum distance between the Start Gate and the Stop Gate should be about 10 cm. The maximum distance between the Start Gate and the Stop Gate should be the maximum provided by the apparatus. You should take 10 or so datapoints for both the streamlined bob and the plastic sphere.
1 of 2
01/04/2003 9:40 AM
Free Fall Summary
file:///F:/lab/1/Videos/FreeFall/FreeFallSummary.html
Make sure that when the streamlined bob is suspended from the magnet that its oscillations have stopped before releasing it. Do not tighten the knob that holds the photogates in place too tightly.
Data Analysis
Putting the data for both the streamlined bob and the plastic sphere into a single dataset is a good idea. A good fit has: The chi-squared statistic approximately equal to the number of degrees of freedom. Residuals that are randomly distributed about zero. A poor fit has: A chi-squared much greater than or much less than the number of degrees of freedom. Residuals that show a systematic deviation from zero. One or more fitted parameters that are zero within
file:///F:/lab/1/Videos/FreeFall/FreeFallSummary.html
Summary of the Free Fall Experiment
This is a summary of the web-based document on the Free Fall experiment at: http://faraday.physics.utoronto.ca/IYearLab/Intros/FreeFall/FreeFall.html. See that document for the complete discussion. Here we summarise that document in a form suitable for printing.
Equations of Motion
In the absence of air resistance:
where: s = the position at time t s0 = the position at time t = 0 v0 = the speed at time t = 0 g = the acceleration due to gravity. When there is air resistance, it is characterised by a constant :
Then the equation of motion is approximately:
The Apparatus
The precision of the metal scale is one part in 4000. The accuracy of the timer is within its reading error of 0.05 msec. The minimum distance between the suspended object and the Start Gate should be about 10 cm. The minimum distance between the Start Gate and the Stop Gate should be about 10 cm. The maximum distance between the Start Gate and the Stop Gate should be the maximum provided by the apparatus. You should take 10 or so datapoints for both the streamlined bob and the plastic sphere.
1 of 2
01/04/2003 9:40 AM
Free Fall Summary
file:///F:/lab/1/Videos/FreeFall/FreeFallSummary.html
Make sure that when the streamlined bob is suspended from the magnet that its oscillations have stopped before releasing it. Do not tighten the knob that holds the photogates in place too tightly.
Data Analysis
Putting the data for both the streamlined bob and the plastic sphere into a single dataset is a good idea. A good fit has: The chi-squared statistic approximately equal to the number of degrees of freedom. Residuals that are randomly distributed about zero. A poor fit has: A chi-squared much greater than or much less than the number of degrees of freedom. Residuals that show a systematic deviation from zero. One or more fitted parameters that are zero within