A freely falling water drop continually evaporates. Assuming that the net momentum carried away by the vapor vanishes, calculate the velocity of the drop as a function of time. (Assume that the rate of evaporation varies as the surface area)[/B]
dA/dr = rate of evaporation, where A is surface area of water droplet...and radius of spherical water droplet.
The Attempt at a Solution
Cant understand what "net momentum carried away by the vapor vanishes" means...cud it be that there r no drag forces the the vapor drop...
. Then how do I find the vel. Of the drop?