What is the Force on a Wall from a Horizontal Water Jet?

AI Thread Summary
The discussion revolves around calculating the force exerted on a vertical wall by a horizontal water jet. The water jet has a velocity of 20 m/s and a cross-sectional area of 5 x 10^-4 m^2, with water density at 1000 kg/m^3. To find the force on the wall, the rate of change of momentum must be determined, considering the water is brought to rest upon impact. Participants are encouraged to clarify their understanding of the problem and share their calculations for part a to assist with part b. The conversation highlights the importance of grasping the theoretical aspects of momentum and force in fluid dynamics.
gidra
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It's my first time writing on this forum, hope I'm posting in the correct section.

Problem :

A hose directs a horizontal jet of water on to a vertical wall.

What is the force on the wall, under the above conditions ? Explain.

Thanks for any replies
 
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Please post the complete problem exactly as it was given.
 
A hose directs a horizontal jet of water, moving with a velocity of 20ms^-1, on to a vertical wall. The cross-sectional area of the jet is 5 x 10^-4 m^2. If the density of water is 1000kg m^-3:

a) fin the rate of change of momentum as the water hits the wall, assuming that the water is brought to rest there;

b) what is the force on the wall, under the above conditions? Explain
 
That's better. Hints for a: How much water hits the wall every second? What's its momentum just before it hits the wall? What's its momentum just after hitting the wall? What's the change in momentum?
 
I worked out part a, I'm stuck with the theoratic part now. Can't really understand the question. Thanks for your replies btw
 
I'm not sure I understand. You completed part a? And you're stuck on part b?
 
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