Explanation for hydrodynamic problem

AI Thread Summary
The discussion revolves around solving a hydrodynamic problem using the Bernoulli and continuity equations. The participant struggles to determine how to calculate the distance the fluid will travel after exiting a hole, despite knowing the fluid's velocity at that point and the height from which it falls. It is clarified that the horizontal acceleration is zero because no forces act on the fluid in that direction after it leaves the hole. The conversation emphasizes applying equations of motion to find time and distance, linking vertical and horizontal movements. Understanding the absence of horizontal forces is crucial for solving the problem effectively.
Mohamed Essam
Messages
24
Reaction score
0
New member advised that an attempt at a solution is required for all homework help requests.

Homework Statement


See the photo of the problem in the attachment

Homework Equations


Bernoulli equation and continuity equation

The Attempt at a Solution


I don't know from where to begin , i only can get the velocity of fluid when it reaches the hole
 

Attachments

  • IMG_0496.jpg
    IMG_0496.jpg
    23 KB · Views: 436
Last edited:
Physics news on Phys.org
You must have been taught something on the topic. Any standard equations relating to fluid flow?
 
haruspex said:
You must have been taught something on the topic. Any standard equations relating to fluid flow?
Yeah , bernoulli equation and continuity equation.
 
Mohamed Essam said:
Yeah , bernoulli equation and continuity equation.
You should have listed those under Relevant Equations in the template.
So try applying Bernoulli's. What do you get?
 
haruspex said:
You should have listed those under Relevant Equations in the template.
So try applying Bernoulli's. What do you get?
Only the velocity of fluid at the hole , i don't know what to do i don't know any other information of how to get the distance x that the fluid will cover
 
Mohamed Essam said:
Only the velocity of fluid at the hole , i don't know what to do i don't know any other information of how to get the distance x that the fluid will cover
That's a good start. (Next time, please show how far you got in your initial post, otherwise you risk having your post deleted.)
If you throw an object horizontally at a known speed and known height, can you figure out where it will land?
 
haruspex said:
That's a good start. (Next time, please show how far you got in your initial post, otherwise you risk having your post deleted.)
If you throw an object horizontally at a known speed and known height, can you figure out where it will land?
I think it's by laws of motion !
 
Mohamed Essam said:
I think it's by laws of motion !
Yes, specifically, motion under constant acceleration. What equations do you know for that?
 
haruspex said:
Yes, specifically, motion under constant acceleration. What equations do you know for that?
D=Vot+1/2at^2
 
  • #10
Mohamed Essam said:
D=Vot+1/2at^2
Right. How can you apply that here?
 
  • #11
haruspex said:
Right. How can you apply that here?
That the problem I've faced , i don't know how to apply it here
 
  • #12
Mohamed Essam said:
That the problem I've faced , i don't know how to apply it here
What facts do you know in this problem regarding speeds, time, distances and accelerations?
 
  • #13
haruspex said:
What facts do you know in this problem regarding speeds, time, distances and accelerations?
I only know the distance from the hole to ground y is 30 cm and the velocity of fluid when it reaches the hole , i only don't know the time when it reaches ground and the acceleration of fluid .
 
  • #14
Mohamed Essam said:
I only know the distance from the hole to ground y is 30 cm and the velocity of fluid when it reaches the hole , i only don't know the time when it reaches ground and the acceleration of fluid .
What is causing it to accelerate, once it has left the tank?
 
  • #15
haruspex said:
What is causing it to accelerate, once it has left the tank?
Only gravity i think
 
  • #16
Mohamed Essam said:
Only gravity i think
Right, so you know the vertical and horizontal (0) accelerations.
Apply your equation for both directions.
 
  • #17
haruspex said:
Right, so you know the vertical and horizontal (0) accelerations.
Apply your equation for both directions.
So i can get the time from the y-direction equation and put it in the x-direction equation so i can get the distance x , is that right ?!
 
  • #18
Mohamed Essam said:
So i can get the time from the y-direction equation and put it in the x-direction equation so i can get the distance x , is that right ?!
Right!
 
  • #19
haruspex said:
Right!
But why you assumed that the horizontal acceleration = 0 , if i didn't know that it equals 0 i can't solve it , so i need to understand why it equals 0
 
  • #20
Mohamed Essam said:
But why you assumed that the horizontal acceleration = 0 , if i didn't know that it equals 0 i can't solve it , so i need to understand why it equals 0
What force is there to accelerate it horizontally?
 
  • Like
Likes Mohamed Essam
Back
Top