



 
Hi Mark, Can you check the measurements you sent? In particular is the paper thickness correct? The numbers just don't make sense to me. Below is what I understand the roll looks like when there are 2,000 linear meters of paper on the roll. Is my diagram correct?
Harley Mark wrote
Mark, I still have problems with the data you sent. Look at the diagram above. The orange region, the edge of the rolled paper, is a region between two circles. The outside circle has a radius of 158.625 + 52.25 = 210.875 mm and the inside circle has a radius of 52.25 mm. The area of a circle is π time the square of the radius so the edge of the rolled paper has an area of
If you unroll the paper the edge forms a long, thin rectangle, 2000 m long by 0.17 mm high. 2000 m is 2000 × 1000 = 2,000,000 mm and thus the area of the edge of the paper is
Thus one calculation of the area of the edge of the paper gives 131,058 mm^{2} and a second gives 340,000 mm^{2}. I can't give you a method to calculate the length of paper remaining on a partially used rool as I don't know what data to use. Harley  


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