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tbdm
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Homework Statement
Suppose we take a 1 m long uniform bar and support it at the 22 cm mark. Hanging a 0.29 kg mass on the short end of the beam results in the system being in balance. Find the mass of the beam.
Homework Equations
[itex]\tau[/itex]=F*r
The Attempt at a Solution
I set it up so that I have the mass of the bar on each end time the gravity for the force of the bar on each end, and add the force of the added mass to the short end, all multiplied by their distance from the point the system is balanced on.
(.22 m)(.29 kg)(9.8 m/s^2) +(.22x)(9.8 m/s^2)(.22 m) = (.78x)(9.8 m/s^2)(.78 m)
And solve for x. Gravity cancels out, and I get x is 0.113928571 kg or approximately 0.11 kg. However this is wrong. I’m not sure what I’m not doing correctly