In a forced draft cooling tower, water is cooled from 95 to 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the

ANS:C - both (a) & (b).

To determine the range and approach in a cooling tower, we need to understand the definitions:

1. Range: The range is the temperature difference between the hot water inlet temperature and the cold water outlet temperature.
2. Approach: The approach is the temperature difference between the cold water outlet temperature and the wet bulb temperature of the air.

• Hot water inlet temperature (Ti) = 95°F
• Cold water outlet temperature (To) = 80°F
• Wet bulb temperature of air (Twb) = 70°F

1. Range: Range = Ti - To = 95°F - 80°F = 15°F
2. Approach: Approach = To - Twb = 80°F - 70°F = 10°F

• The range is 15°F.
• The approach is 10°F.