Chapter 7

Question 1

Humidity

Answer 1

Amount of water vapour in the air

Question 2

How to measure humidity? (units)

Answer 2

Vapour Pressure (e)
Saturated Vapour Pressure (es)
    Unit = mp of Pa
Specific Humidity (q)
Saturated Specific humidity 
    Unit =g/kg
Relative Humidity

Question 3

Vapour Pressure (E)

Answer 3

Portion of total air pressure that results from water vapour molecules (mb). Telling of actual amount of vapour pressure in the air

Question 4

Saturated Vapour Pressure (Es)

Answer 4

The maximum amount of water vapour that the air can hold.

Temperature dependent.

Question 5

Specific Humidity

Answer 5

-

Question 6

Saturated Specific humidity

Answer 6

-

Question 7

Specific Humidity equation

Answer 7

q = mass of water vapour (g)/ mass of air (kg)

Question 8

Relative Humidity equations (3)

Answer 8

e/es *100% = RH

q/qs*100% = RH

(T-Tw) and finding it on the psychrometric table

Question 9

Relative Humidity

Answer 9

• Relative to temperature~!!

Question 10

Humidity Instruments

Answer 10

Hair hygrometer

Sling psychometer

Question 11

Hair hygrometer

Answer 11

Uses bundle strands of human hair held between two brackets, which is attached to a menaism sensing tension from these strands.

Dry hair - shorter. ????

Question 12

Wet bulb temperature (T)

Answer 12

f

Question 13

Wet Bulb Temperature (Tw)

Answer 13

f

Question 14

Wet Bulb Depression (T-Tw)

Answer 14

T-Tw