Question

A glass contains some water at room temperature `20^(@)C`.Refrigerated water is added to it slowly. When the tempareture of the glass reaches `10^(@)C,`small droplets condense on the outer surface. Calculate the relative humidity in the room. The boling point of water at a jprjjessure of 17.5mm of mercury is `20^(@)C`and at 8.9mm of mercury is `10^(@)C`.

Answer 1

Given :
SVF at the dew point = 8.9 mm
SVP at room temperature = 17.5 mm
Dew point = `10^@C` as at this temperature
the condensation starts
Room temperature = ` 20^@C`
` (R_H) = SVP at dew point / SVP at room temp. `
` = 8.9 / 17.5 = 51 %` .