The discussion revolves around determining the appropriate decimal representation of the number 30 given an uncertainty of 0.0625, specifically in the context of using a ruler with 1/8 inch marks. Participants are exploring how to express this measurement while considering significant figures and rounding rules.
The discussion is ongoing, with participants sharing their thoughts on how to handle the uncertainty and significant figures. There is a recognition of multiple sources of error, and some guidance has been offered regarding how to express the measurement, though no consensus has been reached.
Participants are considering the effects of rounding and the precision of the ruler marks, as well as the inherent uncertainties in measurement. There is an emphasis on the need to clarify assumptions about the measurement process.
vvfrn3 said:Significant Digits Ruler -To what decimal point
To what decimal point do I write the number 30 if the uncertainty is 0.0625?
The ruler has 1/8 marks.
Thank you :)
There are three sources of error here. One is that you are rounding to the nearest mark. That introduces an uncertainty of exactly ±0.0625. Next is any error in the placing of the marks on the ruler. You could handle that by rounding the first uncertainty up a little, ±0.064, say. Third is any error in your decision of which is the nearest mark. That's the same in nature as the second error, but statistically independent.vvfrn3 said:I thought it would be 30.000 +- 0.0625 bc there are 3 sig figs in the uncertainty, but I'm not sure. :/
Also, should the uncertainty be rounded since it looks very precise? I'm so confused