## Question

A wire of cross-sectional area *A* at temperature *t* is held taut with negligible tension between two rigid supports. If the wire is cooled to a temperature what tension is developed in the wire? The coefficient of linear expansion is and the Young’s modulus of the wire is *Y*.

### Solution

Let *l *be the length of the wire at temperature *t * and be the contraction in the length as the temperature falls by Then

is

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