Can somebody help me with this question?

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A uniform metre rule of weight 1.2 N rests horizontally on 2 knife edges at the 100 mm mark and 800mm mark. Calculate the support force on the rule due to each knife edge

The CG is at 500 mm and the moments about the pivots are 0 so now it's just a system of equations.

F1 + F2 = 1.2N
(500-100)mm * 1.2N = F2*(800-100)mm


0.514 N at the 100mm point and 0.686 N at th

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It's calculating the moments about the 100 mm pivot point.

(500-100)mm is the arm from the 100 mm point to the CG of the meter stick.

(800-100)mm is the arm from the 100 mm point to the other support point.

These are multiplied by their respective forces and have to be equal to each other.

Combine that with the first equation and you have 2 unknowns (the reaction forces) and 2 independent equations.