Two iron rods have their lengths in the ratio 5:3 and diameters in the ratio 2:1. When the rods are heated from 300C to 1000C the ratio of their expansions is
5:3
3:5
5:6
6:5
given lengths ratio is l1l2 =53 ;diameters ratio is r1r2=21 Δt=sameα=same α=∆ll∆t as Δt=sameα=same ∆l α l substitute the given ratio ∆l1∆l2=l1l2 =53
Does not depend on radius in linear expansion