On heating why aluminium rod expands more than steel rod?:

Hello taiyeba

This is caused by the linear expansion coefficient of different metals (follow this link for more information).

The expansion is related to the binding energy within the atom, and that amount differs for every element.

Thanks sarnian.

The answer you have been given is correct. However, if you are needing help with homework you will attract more answers by posting in homework help under the education thread.

ballengerb1

But this is the homeworkhelp board...
Has the topic been moved there?

Yes it was moved, I do not recall where it was originally posted but it wasn't in the education thread, I think maybe science. Although this is a science question it appears to be mostly someone seeking help with homework.