Is it possible to measure SQRT(2) kg with a scale?

AI Thread Summary
Measuring √2 kg with a scale is deemed impossible due to the irrational nature of the number, but the discussion reveals that the challenge lies in the accuracy of measurement rather than the irrationality itself. Participants argue that any measurement has inherent margins of error, making it difficult to achieve precise results. A proposed method involves constructing a square to create an object with a diagonal length of √2, but this method also faces limitations due to construction errors and thermal fluctuations. Ultimately, while √2 kg cannot be measured directly, approximations may be possible within certain accuracy constraints. The conversation emphasizes the complexities of measurement accuracy and the impact of physical variables on precision.
littlemathquark
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Homework Statement
İs it possible to measure ##\sqrt{2}## kg with a scales?
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Because of ##\sqrt{2}## be a irational numbers I think it is impossible and there is no scales that can measure irational quantity. May be approximately. But 2 kg can be measurable. İt is my efforts and thougts.
 
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littlemathquark said:
Because of ##\sqrt{2}## be a irational numbers I think it is impossible and there is no scales that can measure irational quantity. May be approximately. But 2 kg can be measurable. İt is my efforts and thougts.
It's impossible, but not because the number is irrational. To what accuracy do you propose that this measurement be made? Any measurement is impossible to make beyond a given accuracy.
 
I will offer a counter proposal, make a square with side lengths equal to the unit of your choosing, make an object with the lenght of the diagonal of the square. Now your object has a length of ##\sqrt{2}## units.
 
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pines-demon said:
I will offer a counter proposal, make a square with side lengths equal to the unit of your choosing, make an object with the lenght of the diagonal of the square. Now your object has a length of ##\sqrt{2}## units.
I repeat, to what accuracy?
 
kuruman said:
I repeat, to what accuracy?
As good as your square is. If you make it really straight, thermal fluctuations may average any irregularity out.

Edit: What you are not allowed to do is take a regular scale and try to find ##\sqrt{2}## units in that scale.
 
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kuruman said:
It's impossible, but not because the number is irrational. To what accuracy do you propose that this measurement be made? Any measurement is impossible to make beyond a given accuracy.
If it's impossible for ##\sqrt 2##, then it's impossible for any number. Every measurement has a margin of error.
 
pines-demon said:
Edit: What you are not allowed to do is take a regular scale and try to find ##\sqrt{2}## units in that scale.
I don't see why not. You use your trick to get a length of ##\sqrt 2## and then use that on a scale.
 
pines-demon said:
I will offer a counter proposal, make a square with side lengths equal to the unit of your choosing, make an object with the lenght of the diagonal of the square. Now your object has a length of ##\sqrt{2}## units.
No it doesn’t. You have an object that is ##\sqrt 2## units within the errors of your construction.


pines-demon said:
As good as your square is. If you make it really straight, thermal fluctuations may average any irregularity out.
On the contrary. Thermal fluctuations add to the construction error.
PeroK said:
If it's impossible for ##\sqrt 2##, then it's impossible for any number. Every measurement has a margin of error.
obviously…
 
Orodruin said:
On the contrary. Thermal fluctuations add to the construction error.
There is also thermal expansion.
 
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