A stream of warm water is produced in a steady-flow mixing process by combining 1.0 kg/s of cool water at 25 °C with 0.8 kg/s of hot water at 75 °C. During mixing, heat is lost to the surroundings at the rate of 30 kJ/s. What is the temperature of the warm water stream? Assume the specific heat of water is constant at 4.18 kJ/(kg·K).

Explanation:

The given data is as follows.

      = 0.8 kg/s = 800 g,      

      = 1 kg = 1000 g,   = (75 - T),

      = T - 25

Now, according to the law of conservation of energy,

      + 30000

      250.8 - 3.34T = 4.18T - 104.5 + 30

          T =

              =

Thus, we can conclude that temperature of the warm water stream is .

float.

archimedes' principle

denser than water sinks in water.

denser than mercury would sink in it

the best answer for these questions would be:

1.            c. is smaller

2.            d) concrete operational

3.            b) interaction with the environment – the children interact with their environment can them learn more.

4.            a) parents who reason openly with children can limit a child’s cognitive ability.