How is uncertainty presented in physics?

AI Thread Summary
Uncertainty in physics is often represented by the range between lower and upper bounds based on the precision of the measuring instrument. In this case, a measurement of 5.76 m suggests a range of uncertainty between 5.755 m and 5.765 m, but the measuring tool's precision limits this to 5.75 m to 5.77 m. This discrepancy highlights the importance of understanding how measurement tools affect uncertainty. Additionally, it is noted that humans can estimate measurements within 1/10th of the smallest scale, indicating a natural ability to gauge uncertainty. Overall, clarity on how to define and express uncertainty is crucial in physics.
MBBphys
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Homework Statement


How is uncertainty presented in physics?
If we have:
5.76 m rounded-->wouldn't the range of uncertainty be between the lower and upper bound:
5.755m - 5.765 m
However, my physics teacher said that, as the ruler you are measuring with in this scenario goes down to 0.01 m, you cannot go below that, so the range of uncertainty:
5.75m - 5.77m
Am I confusing lower/upper bound and range of uncertainty here?

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I agree with your interpretation.

At university one of our lecturers told us that humans were actually quite good at estimating to within 1/10th of the smallest scale. In other words if your smallest scale is centimetres then humans are quite good at estimating to within +/- 1mm.
 
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