L1_{1}1 = 100cm, T1_{1}1 = 200∘^{\circ}∘C
L2_{2}2 = 99.4cm,T2_{2}2 = ?
α\alphaα = 2 x 10−5^{-5}−5C−1^{-1}−1
α\alphaα = L2−L1L1(T2−T1)\frac{L_2 - L_1}{L_1(T_2 - T_1)}L1(T2−T1)L2−L1
2 x 10−5=99.4−100100(T2−200)=−0.6100(T2−200)^{-5} = \frac{99.4 - 100}{100(T_2 - 200)} = \frac{-0.6}{100(T_2 - 200)}−5=100(T2−200)99.4−100=100(T2−200)−0.6
2 x 10−5^{-5}−5 x 100(T2−200)=−0.6100(T_2 - 200) = -0.6100(T2−200)=−0.6
T2−200=−0.60.002=−300∘CT_2 - 200 = \frac{-0.6}{0.002} = -300^{\circ}\mathrm{C}T2−200=0.002−0.6=−300∘C
T2=200−300=−100∘CT_2 = 200 - 300 = -100^{\circ}\mathrm{C}T2=200−300=−100∘C