You are walking down to the North Glory Cave to take readings
of the physical environment. It is a hot February day around
midday with a temperature of 330C, very low humidity
of 29% and no wind. As you approach the cave entrance you feel
a cool breeze coming from the cave.These are your readings at
the cave entrance. |
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|
Hygrometers
allow the relative humidity to be calculated. The dry bulb thermometer
is just a normal thermometer recording air temperature. The wet bulb
thermometer has a wet cloth around the bulb. As this moisture evaporates,
it cools the thermometer. To calculate the relative humidity, get
the difference in temperature between the dry and wet bulb, in this
case about 70C. Then go to the dry bulb temperature at
it's reading of 220C. and go across to column 7 at the
top of the table. The relative humidity is 38%. |