q4. (assessment criteria 3.1) state newton's law of cooling and define the terms in the equation. 1. 2. obtain the solution when the initial liquid temperature is 100 c, the ambient temperature is 2 and the thermal time constant is 60 min. 3. plot the solution. remember to label the axis. 4. calculate the fluid temperature after one time constant.

Apreheater involves the use of condensing steam at 100°c on the inside of a bank of tubes to heat air that enters at 1 atm and 25°c. the air moves at 5 m/s in cross flow over the tubes. each tube is 1 m long and has an outside diameter of 10 mm. what is the minimum value of nl needed to achieve an outlet temperature of t 75 c? what is the corresponding pressure drop across the tube bank?