Answer:
estimate the time since construction of the bridge is 6.66 year
Explanation:
given data
area of the plate = 750 cm²
corroded away during use = 2.5 kg
corrosion penetration rate = 0.5 mm/year
density of the alloy = 10 g/cm³
solution
we know here area is express as
CPR = [tex]\frac{kw}{\rho A t}[/tex] ................1
put here value ans we get t
t = [tex]\frac{87.6\times 2.5 \times 10^6}{10\times 750 \times 0.5}[/tex]
t = 58400 hour
time = 6.66 year