Answer:
ΔL = 0.429 m
Step-by-step explanation:
The expression for linear thermal expansion is
ΔL = α L₀ ΔT
the coefficient of linear expansion of steel is 11 10⁻⁶ ºC⁻¹
the initial length of the bridge is L₀ = 1.30 10³ m and the temperature variation is ΔT = 30 ºC
calculate
ΔL = 11 10⁻⁶ 1.30 10³ 30
ΔL = 4.29 10⁻¹ m
ΔL = 0.429 m