Today Puzzle #652
Puzzle No. 652– Monday 13 January
A mobius strip is made by taking a strip of paper, giving it one twist and gluing the ends together. The strip then only has one side, as can be seen if you try to draw a line down its centre. Suppose I have a paper strip that is one centimetre wide. What is the shortest mobius strip that I can make with it, and how long is the centreline?
Today #PuzzleForToday has been set by Hugh Hunt, Reader in Engineering Dynamics and Vibration at Trinity College, Cambridge
Click here for the answer
3.46cm
Or more exactly, 2√3
Such a mobius strip is a flattened-out equilateral triangle, just like the Universal Recycling Symbol â™» . If the tape is unit width the base is 2/√3 so the strip length is 3/√3 = √3. But the centre line goesaround the strip twice so it's length is 2√3.
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