A steel rod of cross sectional area `4cm^2` and length `2m` shrinks by `0.1 cm` as the temperature decreases in night. If the rod is clamped at both ends during the day hours, find the tension developed in it during night hours. Young modulus of steel `=1.9xx10^11 Nm^-2`

Answer

A, C, D

Explanation

`A=4cm^2=4x10^-4, L=2m`
`=/_\L=0.1cm=10^-3, Y=1.9xx10^11`
`Y=F/AxxL/(/_\L)`
`rarr F=(YA/_\L)/L`
`(1.9xx10^11xx4xx10^-4xx10^-3)/2`
`=3.8xx10^4N`
The tension developed is `3.8xx10^4N`