Topic: Heat Transfer
A 10 kg solid at 100 °C with a specific heat of 0.8 kJ/kg C is immersed in 40 kg of 20 °C liquid with a specific heat of 4.0 kJ/kg C. Estimate the temperature after a long time if the container is insulated?
- A. 30 °C
- B. 28 °C
- C. 26 °C
- D. 24 °C
Answer: D. 24 °C
Explanation: Heat lost by solid = Heat gained by liquid. ms * cs * (Ts - T) = mL * cL * (T - Tc). 10 * 0.8 * (100 - T) = 40 * 4 * (T - 20). 800 - 8T = 160T - 3200. 168T = 4000. T = 23.8 °C, which rounds to 24 °C.