The dew point is the temperature at which moist air becomes saturated with water vapor. We can therefore represent how moist a particular parcel of air is by comparing its actual temperature with its dew point temperature.
We see the practical effect of reaching the dew point when on a cold day, we "see our breath" when we exhale.
Suppose it is -10 degrees Celsius outside and our breath leaves our body at 30 degrees Celsius, whereupon it mixes with the outside cold air in a one to one ratio (equal parts warm breath and cold air).
If your breath has sufficient moisture to have a dew point of 24 °C and the outside air has a dew point of -14 °C, will we be able to see our breath after it mixes with the cold outside air?
rs = Ee(T)/p, e = rp/E
The Attempt at a Solution
I am not sure how to go about this. I was thinking something about using the saturation vapor pressure... and I have an idea on the answer, which is that we will be able to see our breath up until we go outside. As being outside, it will try to attain a temperature which is equal to that of air present outside. After mixing, as the dewpoint of outside air is -14oC which is lesser than the outside temperature, hence dewpoint will not be attained, which means that the air from our breath will not saturate. However i need help solving and proving this mathematically. Thank you!
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