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Sat 28 Feb, 2004 10:35 am
hi. i was wondering if you could help me or tell me the answers to these 5 questions. i'm having a tough time finding these answers. thanks!..could you possibly get back to me as soon as possible?..THANK YOU..it would be appreciated!!!
1. Why does water vapor in air condense at the dew point?
2. Infer how the difference in wet and dry bulb temps. measures relative humidity.
3. Some tornadoes are white or transparent rather than gray or black. How can this occur?
4. Why would underground electrical cables be affected by an electrical storm?
5. How do temperature and pressure affect wind?[/B][/B][/color]
1.) Water condenses at the dew point because the air can only hold so much water at a certain temperatures. For example, water at 4C is at it's densist. That is why ice floats, ice is less dense than highly chilled water. So in the air, if the temperature is 5C and it very humid you can bet it's raining. But if the air is dry, it probably won't because there aren't enough water molecules suspended.
3.) White or clear tornado are wind funnels without dust particles. Most tornados only get dark once they touch down and begin sucking up debris.
2. Hmm, difficult to be exact here but in lower relative humidity water will evaporate more quickly thus cooling the thermometer more.
4. Because of enormous electrical and magnetic fields generated by electrical storms. These fields will induce currents in cables.
5. Wind is just air moving from areas of high pressure to areas of low pressure. Temperature affects pressure because of pV=nRT.
Consider "air" as a solution of "air" and water. Then you will be able to make sense of it.
Try this-- In a tablespoon of water see how much common table sugar you can dissolve in it. (it's dissolved when it's clear). When you no longer can "clear" the solution you would call it saturated.
Heat the solution--- Can you add more sugar? How much more sugar can be added to the hot solution?
What happens when it cools?
2. See above. Works the same way, but with the wet bulb you are trying to add more water to a saturated solution.(at 100%humidity) The difference between the two temperatures is regarded as "relative humidity". (How much water is dissolved in the air "relative" to the amount it could "dissolve" at that temperature.) At 100% it becomes dew.
(Or sugar crystals in your experiment)
Buy some "rock candy". Popular in Vermont. The result of your experiment is happiness for your "sweet tooth".