Data: tн (initial temperature of cast iron taken) = 50 ºС; tк (cast iron cooling temperature) = 30 ºС; Q (released heat) = 1 MJ = 10 ^ 6 J; Cch (specific heat capacity of cast iron) = 540 J / (kg * K).
The mass of the cooled cast iron: m = Q / (Сч * (tн – tк)) = 10 ^ 6 / (540 * (50 – 30)) = 92.6 kg.
Answer: 92.6 kg of cast iron should have cooled.
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