2 kg of water at 90 °C is mixed with 3 kg of water at 10 °C. What is the final temperature, assuming no heat is lost?
Answer and explanation
Correct answer: D. 42 °C
- Step 1: Heat lost equals heat gained: °C. Answer: 42 °C. Why not the others: 50 °C, 80 °C and 47 °C don't fit.
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