Egon
Epic Contributor
We don't care if it is 100% accurate. All he asked is if it was fairly close.
And I would say he is close.
For the other stuff. Gravity pulls on the raindrops to make them fall. Raindrop size, wind effects, air resistance and cloud height determine the terminal velocity. The horizontal catchment should collect a representative amount of droplets falling vertically even if they have a horizontal component. If the catchment lip is tilted from the horizontal a reprsentative area is no longer provided. Both horizontal and vertical movement raindrops will be caught. All that should be caught are those under vertical influence.