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Steel balls 12 mm in diameter are annealed by heating to 1150 K and then slowly...

Steel balls 12 mm in diameter are annealed by heating to
1150 K and then slowly cooling to 400 K in an air
environment for which T∞ = 325 K and h = 20 W/m2⋅K.
Assuming the properties of the steel to be k = 40 W/m⋅K,  =
7800 kg/m3 and Cp = 600 J/kg⋅K, estimate the time required
for the cooling process.

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Expert Solution

Amanda K answered 5 months ago
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