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Physics, Astronomy & Cosmology / On what principle does a weighing balance operate?
« on: 28/11/2011 19:06:00 »
A weighing balance (jewellers balance etc.) operates through gravity comparing the torque of the weighed object with a known mass.
The balance arm comes to rest where the acting forces presumably balance. But what are the forces and why do they balance? As one end of the balance drops it gets nearer to the Earth's centre of gravity where gravity is stronger. So why does it not keep dropping?
The balance arm comes to rest where the acting forces presumably balance. But what are the forces and why do they balance? As one end of the balance drops it gets nearer to the Earth's centre of gravity where gravity is stronger. So why does it not keep dropping?