The meter stick, when it is balanced on the table, does not have a torque because each side of the meter stick has a torque, but in opposite directions (clockwise vs counterclockwise), so they cancel out. The center of gravity of the meter stick changes when you add the 100 gram weight, in order to ensure that both sides (when balanced) have the same torque.
To figure out how much the meter stick weighs, we (me and Manuel) measured where the new center of gravity was with the weight, and it was 24.4 cm from the edge of the meter stick. The center of gravity for the meter stick was 50.6 cm. We had to find the torque of one side of the meter stick, so we used the one with the weight on it, where we knew both the force downward (9.8 times .1) and the lever arm (.24). Using those numbers, we got the torque as .239 N. We then plugged that number into the other side, with the equation .239=(.506-.244)(Force), with Force being the weight of the meter stick.
With this equation set up, all we had to do was solve it, then convert the answer from .912 Newtons, to grams, which gave us the answer of 92.85 grams. The actual weight was 92.1 grams.
(Labelled drawing in progress)
You did very well on showing your process, and it was very helpful that you showed your actual work. I would recommend putting labeled pictures in this post. If you need some to look at while studying, you can go to my blog and see the pictures I made
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