Engineering Board Exam Reviewer · Thermodynamics · medium
How much heat is needed to raise the temperature of 5 kg of water from 20 °C to 80 ° C? (c = 4.187 kJ/kg· K)
- 1674.8 kJ
- 1256.1 kJ
- 251.2 kJ
- 2093.5 kJ
Answer
B. 1256.1 kJ
Solution
Q = mc T = 5(4.187)(80 - 20) = 1256.1 kJ.
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