In Exercise 9, what would the distance across the top of the worm thread have to be to make d equal to 0 inches?

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1 Answer
Jan 25, 2018

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When d=0 inches the situation will be represented by the modified figure as shown above. The distance across the top of the worm thread then will be PR

Now PR=2PQ=2PQOQ×OQ

PR=2PQOQ×(QC+CQ)

PR=2PQOQ×(QC+CQCN×CN)

PR=2PQOQ×(CN+CQCN×CN)

PR=2PQOQ×CN(1+CQCN)

PR=2tanθ×0.75(1+cscθ)

PR=1.5(tanθ+tanθ×cscθ)

PR=1.5(tanθ+secθ)

PR=1.5(tan15+sec15)1.95 inch