Answer:
9.949 m
Explanation:
From the question,
L' = L+LαΔT................. Equation 1
Where L' = New length, L = Original length, α = linear expansivity of Cu, ΔT = change in temperature
Given: L = 10 m, α = 0.00017 K⁻¹, ΔT = 50-80
L' = 10+10(0.00017)(50-80)
L' = 10-0.051
L' = 9.949 m
Hence the new legth of Cu is 9.949 m
