On a vertical plane, width $1m,$ a film of $1200kg{h}^{-1}$ of water flows

downwards. Find expressions for the mean velocity using momentum

and mass balances. Use these to then find the film thickness and

hence the mean flow velocity and the maximum velocity?

Ans. $4\mathrm{.}7{10}^{-4}m,0\mathrm{.}71m{s}^{-1},1\mathrm{.}07m{s}^{-1}.$