Question

1. A piece of material thickness t is wrapped n times around a cylinder of radius r, as is shown in Fig.1 (for 4). What is the total length of material required? 1) Derive a simple equation for the length of material required for n wraps. Assume that the material forms n concentric circles 2) Explain why this model might not be sufficiently accurate, and derive an im- proved equation. You do have to evaluate your equation if it is too complicated, but you should explain your derivation carefully and why it is better than the model in previous part. 3) Explain in what situations your improved equation would give a relatively similar and relatively dissimilar answer to the results from the first part Figure 1 An illustration for Question 1

Answer 1

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