(a) A wire that is 1.50 m long at 20.0°C is found to increase in length by 1.90 cm when warmed to 420.0°C. Compute its average coefficient of linear expansion for this temperature range. (b) The wire is stretched just taut (zero tension) at 420.0°C. Find the stress in the wire if it is c??led to 20.01°C without being allowed to contract. Young’s modulus for the wire is 2.0 × 1011 Pa.

Solution 23E a) The coefficient of linear expansion is defined mathematically as, L= L T ------------------(1) 0 Where L i0 the initial length. L is the change in length due to temperature change. T is the change in temperature. So, as we know the initial length, change in length, initial and final temperatures, let’s calculate the expansion coefficient. = 1 L = 1 × 0.019 L L0T 1.50 42020 = 1 × 0.019= 0.00003166 = 3.166 × 10 5 1.50 400 CONCLUSION: 5 The coefficient of linear expansion is 3.166 × 10 . b) The young’s modulus is...