question: a composite bar of length L=L1+L2 is made from a bar of material 1 and length L1 attached to a bar of material 2 and length L2.(adsbygoogle = window.adsbygoogle || []).push({});

show that the effective coefficient of linear thermal expansion is :

alpha= (a1L1+a2L2)/L

[- alpha/a=coefficient of linear thermal expansion]

i have no idea how to derive that equation, the only thing i no/learned from reading the book is that the equation for the coefficient of linear thermal expansion for one material is alpha=(delta L)/Lo(delta T)

anyone who can show me/drop some hints would be greatly appreciated.

thanks in advance

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Coefficient of linear thermal expansion of a composite bar

**Physics Forums | Science Articles, Homework Help, Discussion**