A metal rod has a length of 100cm at 200oC. At what ...
A metal rod has a length of 100cm at 200oC. At what temperature will its length be 99.4cm. If the linear expansivity of the material of the rod is 2 x 10−5C−1
200oC
300oC
100oC
-100oC
Correct answer is D
L1 = 100cm, T1 = 200oC
L2 = 99.4cm,T2 = ?
α = 2 x 10−5C−1
α = L2−L1L1(T2−T1)
2 x 10−5=99.4−100100(T2−200)=−0.6100(T2−200)
2 x 10−5 x 100(T2−200)=−0.6
T2−200=−0.60.002=−300oC
T2=200−300=−100oC