Engineering Board Exam Reviewer · Thermodynamics · hard
A 0.5-kg copper block (c = 0.385 kJ/kg· K) at 200 °C is dropped into 2 kg of water (c = 4.187 kJ/kg· K) at 25 °C in an insulated container. What is the final equilibrium temperature?
- 112.50 °C
- 60.00 °C
- 28.93 °C
- 33.93 °C
Answer
C. 28.93 °C
Solution
0.5(0.385)(200 - T) = 2(4.187)(T - 25) T = [38.50 + 209.35]/[0.1925 + 8.374] = 28.93 ° C.
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