For this lab the force was clearly defined and even calculated for you at the top of the data table for run 1. It is the hanging mass x g = .1 kg x 9.8N/kg ( use 9.8 for labs) =.98 N for Run 1. Force for run2 = .05 kg x 9.8 N/kg = .49 N. The slope you find from your graphs is not force, it is Ma. You were supposed to compare your slope with the force ( .98 N or .49 N depending on the run). If you found your acceleration in cm /s^2 and graphed it without dividing by 100 to get m/s^2 then you need to divide your slope by 100 to compare with the force in N since 1 N is 1 kg m/s^2 NOT 1kg cm/s^2.
Some of you found the force as if the hanging mass were 100 kg instead 100 g = .1 kg. This gives a force that is a factor of 1000 high.
Some of you found the slope and called it the force and then divided it by mass and got your acceleration. This does not prove F= Ma. It proves that Ma/M =a, something that is pretty well established .
To repeat the most important point: you must compare your slope in units of kg m/s^2 with the force ( .98N or .49N) that was accelerating the system.
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