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firefox
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I'm currently completing an Atwood Machine Experiment with two 100g weights on either side of the pulley, with a variance in weight created by attaching dimes and pennies to either side of the weights. The point of the experiment is to validate:
(m1 – m2)g = (m1 + m2 + I/R2)
The experiment involved varying the weights between the sides and timing how long M1 takes to hit the ground from being dropped from a height where m2 is just hovering above the ground. This was my data.
http://puu.sh/nYt7k/cef6642fe9.png
n represents the number of dimes attached to the bottom of m2. As the number decreases, the dimes removed are added to the m1 side.
height from pulley to ground: 0.31m
pulley radius: 0.025m
m1g - T1 = m1 a
T2 - m2 g = m2 a
(T1-T2) R = Iα
From this system:
(m1 - m2)*g = (m1 + m2 + I/R2 )*a
To graph the results, we can use:
y= (m1-m2)g
mx = (m1 + m2 + I/R2 )*a
http://puu.sh/nYtGJ/5ebdb6e1a8.png
Trendline equation for (m1-m2)g vs a: y= 194.179672x + 47.74182125
Moment of Inertia was calculated using: slope = (m1 + m2 + I/R2 )
when solving for inertia by using the slope of the graph created by the a as the independent axis and (m1-m2)g as the dependent axis, I get a negative number. I'm quite lost at this point and I'm not sure how to proceed. It doesn't make sense to me that inertia is negative. Could this be because I'm not accounting for the fact that the y intercept isn't 0 in our combined inertia equation?
Thanks in advance for the help,
Firefox
(m1 – m2)g = (m1 + m2 + I/R2)
Homework Statement
The experiment involved varying the weights between the sides and timing how long M1 takes to hit the ground from being dropped from a height where m2 is just hovering above the ground. This was my data.
http://puu.sh/nYt7k/cef6642fe9.png
n represents the number of dimes attached to the bottom of m2. As the number decreases, the dimes removed are added to the m1 side.
height from pulley to ground: 0.31m
pulley radius: 0.025m
Homework Equations
m1g - T1 = m1 a
T2 - m2 g = m2 a
(T1-T2) R = Iα
From this system:
(m1 - m2)*g = (m1 + m2 + I/R2 )*a
To graph the results, we can use:
y= (m1-m2)g
mx = (m1 + m2 + I/R2 )*a
The Attempt at a Solution
http://puu.sh/nYtGJ/5ebdb6e1a8.png
Trendline equation for (m1-m2)g vs a: y= 194.179672x + 47.74182125
Moment of Inertia was calculated using: slope = (m1 + m2 + I/R2 )
when solving for inertia by using the slope of the graph created by the a as the independent axis and (m1-m2)g as the dependent axis, I get a negative number. I'm quite lost at this point and I'm not sure how to proceed. It doesn't make sense to me that inertia is negative. Could this be because I'm not accounting for the fact that the y intercept isn't 0 in our combined inertia equation?
Thanks in advance for the help,
Firefox
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