Question

on doubling the length of rod, what will be the change in its expansivity

Answer 1

Now from linear expansion we know

Alfa = change in length/ length× change in temperature

i.e. alfa = 2L-L/ L×( T`-T)

Or (T`-T) × L = L /Alfa

Or (T`-T) = 1/ Alfa

i hope it will helps you friend