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Cavendish

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Date: Mon, 27 Sep 2021 15:35:08 -0700 (PDT)
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Subject: Cavendish
From: carleto4...@gmail.com (carl eto)
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by: carl eto - Mon, 27 Sep 2021 22:35 UTC

How did Cavendish derive Newton's constant using a 10^-8 kg force since the minimum uncertain of a scale in 1790 was 1 mg?

Profile photo for Peter Upton
Peter Upton
, BA Physics & Mathematics, The Open University
Answered 6m ago
Strictly 1mg is a mass not a force but the uncertainty in weight measurements would have been 10^-3 g ie about 10^-2 N.

However Cavendish did not measure force by using a balance. There wwere no masses involved in the foce measurement.

He measured the force by measuring the deflection of a torsional spring ( a wire).He basically used ideas like F=kx and determined the constant k for his spring (wire) by means of another calibration experiment which involved setting the spring /mass system into oscillation

Just to be certain, if you are worried about the uncertainties in the masses, then thie would have been soeming like 1mg in lets say 1kg. THis would correspond to an uncertainty in the mass of about 0.0001% or 0.000001

There's got to be more to life than compile-and-go.

tech / sci.physics.relativity / Cavendish

tech / sci.physics.relativity / Cavendish