A metal meter scale gives correct measurement at 400C it is generally used at a temperature of 00C . Find the correction to be made for every meter α=10−6/0C
4×10−5m
4×10−5mto be added
4×10−5mmust be deduted
none of the above
change in length is Δl=lαΔt l is initial length of rod =1m;α is coefficient of linear expansion=10-6/C 0 Δt is change in temperatue; decreased from 400C to 00C Δl=1×10−6×40 Δl=4×10−5m
If t2<t1 so correction must be deducted.