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A mild steel ball of diameter 1.2 cm is initially at a temperature...

Q.  
A mild steel ball of diameter 1.2 cm is initially at a temperature of 873 K and is exposed to air at 300 K. Find the time needed to cool the steel ball to 368 K. Assume that the convection heat transfer coefficient is 0.114 kW/m2 K. Also find the heat transfer rate after 120s.


Answer & Explanation

Answer :   Option: A


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Answer & Explanation
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