The CAUSE OF THE MOTION OF A FIRE HOSE

AI Thread Summary
The discussion centers on the motion of a fire hose when water is expelled from its nozzle, specifically exploring the underlying causes of this motion. Key concepts include inertia and the conservation of energy and momentum, which explain the hose's behavior as it reacts to the water jet. Participants mention the importance of understanding the dynamics involved, including the hose's initial position and water flow rate. There is also a reference to a video demonstrating the phenomenon, although technical issues prevent its sharing. The thread concludes with a note on the complexities of the hose's motion, likening it to the oscillation of a pendulum.
Shabdar
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ok thank you

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1. Homework Statement

suppose we have fire hose with water jet coming out of its nozzle. we'll see a subsequent motion. what is the cause of this motion?


2. Homework Equations

I haven't yet got to calculation past but I know angular velocity is the reason why this phenomenon happens in the first place.

3. The Attempt at a Solution

I've so far read a paper about this, in which a group of students had investigated the relevant parameters and found their effect on the phenomenon. I've also seen the phenomenon with different water hoses and different water pressure in them.
I have an idea why the first turning motion happens but I do not know the reason why it happens (turns) in the opposite way.

this is one of the questions of the IYPT (International Young Physicists Tournament).
here is the link that shows we have the permission to research the internet or talk to experts;
http://en.wikipedia.org/wiki/Interna...39;_Tournament
(last line in the "The Problems" part)

Also, The name of this website and the name of the expert who helps me will be mentioned in my references part in the tournament.

there is a movie I've recorded in a gas station. I can't upload it here because its too big. I can email it if anyone wants.


Shabdar said:
Consider we have a fire hose with water jet coming out of it's nozzle. When we release the hose, we'll see a subsequent motion. what is the cause of this motion?

Shabdar said:
Dear Berkeman,
This is one of the questions of the IYPT competition, in which students are free to research about the questions in any way they want. I apologize if I didn't know this must go in the homework category.
I'd appreciate it if you'd tell me where the homework part is because I do not know.

Shabdar said:
Dear Berkeman,

I apologize for bothering you again.
I just realized that everyone can see the questions I ask. since I don't want other competitors to know about this, I would appreciate it if you could delete that thread please.

Sincerely Yours,
Shabdar
 
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suppose we have fire hose with water jet coming out of its nozzle. we'll see a subsequent motion. what is the cause of this motion?
Inertia law - conservation of energy and momentum - details depend on the particular motion of interest. You mean a coiled fire hose on the wall?

I think we need to see the original question.
 
Dear Simon Bridge,

Thank you for your reply.
not really. the fire hose is on the floor. how can I show you the video I've recorded?
 
You can upload the video to some website and link to it.
If you encode it ogg/theora you can use:
http://en.flossmanuals.net/ogg-theora/putting-it-online/hosting-sites/
... though youtube is a fave.

note: a random oriented nozzle on the floor will whip back and forth - the cause is similar to how a pendulum goes back and forth. The rest of the coils will move according to how the water moves through them (and the head moves). The water may not be moving at a constant flow rate either.
 
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kjjjii
 
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