Question

Three liquids of equal volumes are thoroughly mixed. If their specific heats are s₁, s₂, s₃ and their temperature q₁, q₂ , q₃ and their densities d₁, d₂, d₃ respectively, then the final

temperature of the mixture is –

• A. $\frac{s_{1}\theta_{1} + s_{2}\theta_{2} + s_{3}\theta_{3}}{d_{1}s_{1} + d_{2}s_{2} + d_{3}s_{3}}$
• B. $\frac{d_{1}s_{1}\theta_{1} + d_{2}s_{2}\theta_{2} + d_{3}s_{3}\theta_{3}}{d_{1}s_{1} + d_{2}s_{2} + d_{3}s_{3}}$
• C. $\frac{d_{1}s_{1}\theta_{1} + d_{2}s_{2}\theta_{2} + d_{3}s_{3}\theta_{3}}{d_{1}\theta_{1} + d_{2}\theta_{2} + d_{3}\theta_{3}}$
• D. $\frac{d_{1}\theta_{1} + d_{2}\theta_{2} + d_{3}\theta_{3}}{s_{1}\theta_{1} + s_{2}\theta_{2} + s_{3}\theta_{3}}$

Answer 1

Answer: (B)

$\frac{d_{1}s_{1}\theta_{1} + d_{2}s_{2}\theta_{2} + d_{3}s_{3}\theta_{3}}{d_{1}s_{1} + d_{2}s_{2} + d_{3}s_{3}}$

Answer 2

\ Q_mix = $\frac{m_{1}s_{1}\theta_{1} + m_{2}s_{2}\theta_{2} + m_{3}s_{3}\theta_{3}}{m_{1}s_{1} + m_{2}s_{2} + m_{3}s_{3}}$\ m = rV