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2 years ago

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A thick steel sheet of area 150 in.2 is exposed to air near the ocean. After a one-year period it was found to experience a weig

ht loss of 485 g due to corrosion. To what rate of corrosion, in (a) mpy and (b) mm/yr, does this correspond? The density of steel is 7.9 g/cm3.

1 answer:

Bingel [31]2 years ago

5 0

Answer:

Rate of corrosion = 24.95 mpy

Rate of corrosion = 0.63 mm/yr

Explanation:

given data

steel sheet area = 150 in²

weight loss = 485 g

density of steel = 7.9 g/cm³

time taken = 1 year

to find out

rate of corrosion in (a) mpy and (b) mm/yr

solution

we get here the rate of corrosion that is express as

rate of corrosion = (k × W) ÷ (D × A × T) ..................1

here k is constant and w is total weight lost and t is time taken for loss and A is surface area and D is density of steel

so put her value in equation 1 we get

Rate of corrosion = $\frac{534*485*1000}{7.9*150*24hr*365day/yr}$

Rate of corrosion = 24.95 mpy

and

Rate of corrosion = $\frac{87.6*485*1000}{7.9*150*2.54^2*24hr*365days/yr}$

Rate of corrosion = 0.63 mm/yr

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