Answer:
ΔLa/ΔLb = 1
Step-by-step explanation:
The change in length of a solid is given by the following formula:
ΔL = α L ΔT
where,
ΔL = Change in length
α = coefficient of linear expansion
L = Original Length
ΔT = Change in Temperature
Since, the length and change in temperature for both rods are same. Also, the material of each rod is same, which implies that coefficient of linear expansion for both rods is same. Hence, the ratio of change in length of both rods will be:
ΔLa/ΔLb = 1