How do you find Relative Humidity? I don't get how to do it!!!?

Question

OK. My sister has a HUGE science test tomorrow and we need to know how to find relative humidity and dew point..she gets a chart on the test but she has to know how to find the answer.

PLEASE HELP AND HURRY!!!!!!!!

Answer 1

You measure the temperature of the air and then wrap a thermometer with a wet towel and spin it in the air for few minutes. You will notice the wet towel gets cold from the spinning because water evaporates and cools and so on-anyway, the temperature of the wet towel is the wet bulb temperature of the air. The ratio of the two temperatures you have is the relative humidity.

Answer 2

it the differnece between wet and dry bulb subtracxt them