- #1
RJWills
- 16
- 0
Homework Statement
"A composit bar is made of two metals joined in series, with coefficients of linear thermal expansion 2.2E-5 and 0.9E-5 K^-1 respectively. The bar expands by 0.5% in length with a temperature rise of 500 K. Calculate the ratio of the initial lengths of the two metal sections."
Homework Equations
The main equation I think to be useful is ΔL=α L ΔT
The Attempt at a Solution
I am thinking that I cannot assume that the two bars will expand the same amount, meaning that the sum of ΔL1+ΔL2+L=1.005L...
500(ΔL1α1+ΔL2α2)+L=1.005L
500(ΔL1α1+ΔL2α2)/L=0.005
Whatever way I look at this I just see myself going round in circles :/