Question
Physics Question on thermal properties of matter
A steel tape is calibrated at 20∘C. when the temperature of the day is −10∘C , the percentage error in the measurement with the tape is α=12×10−6/∘C)
A
0.036
B
0.0036
C
0.0018
D
0.00036
Answer
0.00036
Explanation
Solution
We know, l2=l1(1+αdt) where dt= change in temperature =30∘C The percentage error in the measurement will be, (dl/l) X10o =α dt 100=12×30×100×10−6 =36×10−3=0.036%