Chapter 7, Problem 10P

The relative humidity, RH, at sea level can be calculated from measured values of the dry-bulb temperature, T_db, and the wet-bulb temperature T_wb by (temperatures in degrees Celsius):

$RH=\frac{VP}{SVP}100$

where VP is the vapor pressure given by: VP

$VP=e\frac{16.78T_{wb}-116.9}{T_{wb}+237.3}$

$-0.066858(1+0.00115T_{wb})(T_{db}-T_{wb})$ and

SVP is the saturated vapor pressure given by:

$SVP=e\frac{16.78T_{wb}-116.9}{T_{wb}+237.3}$

Write a user-defined function for calculating RH for given T_dband T_wb. For the function name and arguments, use RH = RelHum(Tdb,Twb). The input arguments are Tdb and Twb are the dry-bulb and wet-buld temperatures, respectively in °F. The output argument RH is the relative humidity in percent (rounded to the nearest integer). Inside the user-defined function use a subfunction. or an anonymous function to convert the unit of the temperature from Cesius to Fahrenheit. Use the function to determine the relative humidity for the following conditions:

(a) T_db=75°F, T_wb=69°F. (b) T_db=93°F, T_wb=90°F.