R-1

One hundred cu ft of air at 70 F dry bulb and 20 per cent relative humidity are passed through a spray chamber where it comes in contact with water at the adiabatic-saturation temperature. It is cooled adiabatically and leaves at 53 F. What is the final percentage saturation of the air and how much moisture does it pick up?

R-2

In a drying process air at 70 F and 60 per cent relative humidity enters the dryer and is discharged at a temperature of 90 F and 90 per cent relative humidity. How many cubic feet of air must be circulated through the dryer to remove 10 lb of water per min from the material to be dried? Note that a cubic foot of entering air has a greater volume on leaving.

R-3

An air-conditioning engineer has been given the following data on a room to be air conditioned:

1. Calculate the refrigeration tonnage required with 10 per cent safety factor.

2. Calculate the dry - and wet-bulb temperature of a mixture of 25 per cent outside air and 75 per cent return air.

3. Calculate the room sensible heat factor and apparatus dew point.

4. Calculate the cfm supply of air to satisfy room requirements.

R-4

A conditioner cooling surface fin section has a total capacity of...