How can you explain how a balance works vectorially?

AI Thread Summary
A balance with equal weights on both arms remains horizontal due to equal forces acting at 10 N each. When tilted at 45º, the vertical force becomes cos 45 * 10 N, suggesting the balance should remain in that position. However, there is a tendency for the balance to level back to horizontal, which contradicts basic physics principles. The discussion highlights that vector analysis fails to accurately explain the behavior of the balance, particularly in non-ideal conditions. Ultimately, the forces from the central support become asymmetrical when tilted, affecting the balance's stability.
eosphorus
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you have a balance with 1kg weight in each 1 meter long arm

when its horizontal each 10 N force * 1 m long will balance so the balance won't move

but when you lean the balance 45º the vertical force will be cos 45 * 10 N in each arm so the balance should stay in that position since the forces are equal but it tend to level horizontal

can anyone explain this please
 
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All I can do is ask where you got the idea that a balance in such a situation would tend to leve!
 
its not only what basics physics say but besides i have tested it myself in case that basic physics were wrong
 
I am betting it has to do with the force between the ballance and the central support. I am guessing, that in your (non-ideal) experiment the force from the support is no longer symmetrical once the balance is tilted.
 
im afraid i disagree basic physics says a balance will balance or level with equal weights in its arms

the problem is that you can't prove it vectorially what doesn't mean the balance won't level simply vectors fail to explain a simple physical process
 
besides if you put 1kg in one arm and 2 kg in the other arm and aply vectors the balance will tend to put vertical according to vectors but balances don't behave that way

i insist vectors fail to explain how a balance works
 
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