Force exerted by water in a U-shaped tube

[Dansuer]

Homework Statement

In a U-shaped tube, water is flowing with velocity v. The flowing rate is u, and it's constant. What force does the water exert on the wall of the tube.

Homework Equations

F = dp/dt

u = m/t

The Attempt at a Solution

The change in momentum is
$mv - (-mv)$

or

$2uv \Delta t$

so

$F = 2uv$

is this correct?

 

[vela]

Yes, that's correct.

 

[Dansuer]

Thanks a lot !