Question

A steel wire 2mm in diameter is stretched between two clamps, when its temperature is `40^@C` Calculate the tension in the wire, when its temperature falls to `30^@C` Given, coefficient Y for steel ` = 21 xx 10^(11) dyn e//cm^2`

Answer 1

Correct Answer - `7.26xx 10^6dyn e`
`Delta l = l alpha(theta_2- theta_1)`
` = lxx(11 xx 10^(-6))xx (40 - 30)cm.`
`Now, F = (Y A Delta l)/(l) = (Ypi r^2 Delta l)/(l)`