Chapter 1, Problem 121P

A $\text{4}-m\times 5-m\times 6-m$ and room is to be heated by one ton (1000 kg) of liquid water contained in a tank placed in the room. The room is losing heat to the outside at an average rate of 10,000 kJ/h. The room is initially at ${20}^{\text{o}}\text{C}$ and 100 kPa and is maintained at an average temperature of ${20}^{\text{o}}\text{C}$ and at all times. If the hot water is to meet the heating requirements of this room for a 24-h period, determine the minimum temperature of the water when it is first brought into the room. Assume constant specific heats for both air and water at room temperature.