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## Homework Statement

Water flows at a speed of 0.75 m / s through a U-shaped tube whose cross-section is circular with a radius of 10 mm. How large is the force F to be to compensate for water power on the tube?

## Homework Equations

I am not sure. Perhaps;

Pressure=Force/Area

Conservation of momentum

Density = mass/volume

## The Attempt at a Solution

I believe that the

**speed**of water flow is the same through the whole pipe but the velocities have different signs in each side of the pipe. Of course the mass is constant.if I use conservation of momentum I will have:

Fdt=m(Δv)=m(v_1-v_2)=m(v-(-v))=2mv

Fdt=2mv. The mass is not given but if we knew the volume we could find it as m=ρV. And how can I separate F from Fdt?

I tried this(wrong);

**F**dt=2m

**v**=2m(d

**x**/dt) --->

**F**=2m(d^2

**x**/dt^2)=2m

**a**=0 since velocity is constant.