Initial data: Q (amount of heat) = 8.5 kJ = 8500 J, t1 (initial temp.) = 80 ºС, t2 (final temp.) = 20 ºС.
Constants: C (specific heat), options: a) C1 (copper, zinc, brass) = 400 J / (kg * K); b) C2 (steel) = 500 J / (kg * K); c) C3 (cast iron) = 540 J / (kg * K);
To calculate the mass of the part, we will use the formula:
Q = C * m * (t2 – t1).
m = Q / (C * (t2 – t1)).
a) m1 = 8500 / (400 * (80 – 20)) = 0.354 kg.
b) m2 = 8500 / (500 * (80 – 20)) = 0.283 kg.
c) m3 = 8500 / (540 * (80 – 20)) = 0.262 kg.
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