Error in Wikipedia Cavendish article

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SUMMARY

The forum discussion centers on the accuracy of the force measurement attributed to Cavendish in the Wikipedia article, which states he measured a force of 1.74E-7 N, equating to the weight of a large grain of sand at 0.13 mg. Calculations using the formula m=F/g reveal that this weight should actually be approximately 0.0177 mg, significantly less than the Wikipedia claim. The discrepancy suggests that the article may have overstated the weight by a factor of 7.3, raising questions about the feasibility of Cavendish's measurements given the challenges of air resistance and mechanical friction in his apparatus.

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waverider
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According to Wikipedia, Cavendish was able to measure a force of 1.74E-7 N or “roughly the weight of a large grain of sand[13] of 0.13 mg”

However, with my calculations using m=F/g, where g=9.81m/s/s

Gives m=1.74E-7/9.81 = 1.77E-8 kg = 0.0177 mg

Which is much less than 0.13 mg

Am I missing something?
 
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Let's see...

0.13 mg = 0.00013 g = 0.00000013 kg = 1.3x10^-7 kg
F = MG
F = 1.3x10^-7 * 9.81
F = 1.28x10^-6 Newtons

Hmm... you appear to be correct.
Perhaps it should be a small grain of sand?
 
Indeed, the Wikipedia weight is 7.3 times higher.
I find it impossible that Cavendish was able to measure such a tiny force of attraction between the metal spheres and this force was able to overcome the air resistance and mechanical friction which was apparent in the apparatus.
 
What air resistance and mechanical friction?
 

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