Problem 133P

An air-conditioning system operates at a total pressure of 1 atm and consists of a heating section and an evaporative cooler. Air enters the heating section at 15°C and 55 percent relative humidity at a rate of 30 m3/min, and it leaves the evaporative cooler at 25 °C and 45 percent relatively humidity. Determine (a) the temperature and relative humidity of the air when it leaves the heating section, (b) the rate of heat transfer in the heating section, and (c) the rate of water added to air in the evaporative cooler.

Natural or Counting Numbers : {1,2,3,4,5,…} "0" is NOT one of them a. Natural numbers start w/ "1" and continue on to infinity Whole Numbers: {0,1,2,3,4,5...} a. Whole numbers start with "0" and continue on to infinity b. NO fractions Integers: { …-3,-2,-1,0,1,2,3...} a. These are whole numbers (0,1,2,3,…) with negative #s included Rational Numbers: any # which can be written in form of a/b (fraction) a. ½ b. - ½ c. .33 = 1/3 d. .66 = 1/6 Prime Numbers: #s that can ONLY be divided by "1" and itself a. CANNOT be an even number (2, 4, 6, 8...) b. 1, 7, 11, 13... Composite #: has more than "1" as a factor a. 4 = 2, 2 b. 6 = 2, 3 c. 9 = 3, 3 Commutative Property: think of the word "commute" - same distance to and