Q 11-10-035NEETJEE MainEAMCET 2000 (Engineering)Easy
Two liquids at temperatures $60°$C and $20°$C respectively have masses in the ratio $3 : 4$ and their specific heats in the ratio $4 : 5$. If the two liquids are mixed, the resultant temperature is
Answer: (D) $35°$C
Heat lost = heat gained:
$$3 \times 4\,(60 - \theta) = 4 \times 5\,(\theta - 20) \;\Rightarrow\; 720 - 12\theta = 20\theta - 400 \;\Rightarrow\; \theta = 35°\text{C}$$
Solution by Sreeraj P, M.Sc Physics