Question
Question: Length of a wire at room temperature is \(4.55\) m, when the temperature increases upto \(100^{o}C\)...
Length of a wire at room temperature is 4.55 m, when the temperature increases upto 100oC then its length becomes 4.57 m. the coefficient of linear expansion. (α) of the given wire is.
A
5.021×10−5K−1
B
6.021×10−5K−1
C
7.021×10−5K−1
D
8.021×10−5K−1
Answer
6.021×10−5K−1
Explanation
Solution
Here, T1=27∘C=273+27=300l
L1=4.55m,L2=4.57m
As, L2=L1[1+α(T2−T1)]
∴4.57=4.55[1+α(373−300)]
4.57=4.55[1+α×73]
Or α=[4.554.57−1]×731=[4.554.57−4.55]×731
α=6.021×10−5K−1