Q.

A brass wire of length 2 m and radius 1 mm at 27°C is held taut between two rigid supports. Initially, it was cooled to a temperature of -43°C creating a tension T in the wire. The temperature to which the wire has to be cooled in order to increase the tension in it to 1.4T, is _________ C.               [2026]

1 - 80  
2  - 65  
3 - 71  
4 - 86  

Ans.

(3)