Fluid Mechanics and SHM of spring

AI Thread Summary
The discussion centers on two physics problems: one involving fluid mechanics and the other simple harmonic motion (SHM) of a spring. The fluid mechanics problem requires calculating the velocity of water in a narrowing pipe using Bernoulli's principle and the continuity equation, with a focus on expressing velocity in terms of tank height. The SHM problem involves determining the amplitude and phase constant of a block displaced from its original position, but there is confusion regarding the absence of the spring constant in the calculations. Participants emphasize the need for clearer problem statements and express concerns about solving the SHM problem without essential parameters. The conversation highlights the importance of understanding fundamental principles in both fluid mechanics and SHM.
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Homework Statement


Fluid Mechanics problem: http://i.imgur.com/dlAO6.jpg

SHM of spring problem: http://i.imgur.com/7AOMR.jpg

Homework Equations


Fluid mechanic problem;
Bernoulli's principle A1v1=A2v2
v= velocity
A= cross sectional area
R= flow rate

SHM of spring problem;
x(t)=Acos(ωt+∅)

The Attempt at a Solution


For the Fluid problem I ended up with :
v = R/A2 = 2R/A1

For the SHM problem I ended up with:
A = 0.10
∅= cos-10.05/0.1I'm having a problem with both of these problems and I'm not confident with my answers.
Any help would be greatly appreciated :)
(And sorry if I break any rule of the forums or such, It's only my first post :/ )
 
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You are going to have to provide a better problem statements than what you supplied. We are not mind readers here.
 
LawrenceC said:
You are going to have to provide a better problem statements than what you supplied. We are not mind readers here.

I'm sorry :/ These problems are actually made by my professor himself, but I'll try to explain.

In the first problem, water is flowing from the tank into a narrowing pipe, I'm supposed to get the velocity of the water when its in the narrow part of the pipe. It's related to Bernoulli's principle of fluid through a narrowing pipe.

For the second problem, It's a block of 0.5 kg displaced 5cm from its original position with an initial velocity of 10 m/s. I'm supposed to get A (or Xm) which is Amplitude and ∅ which is the phase constant.
 
In the fluids problem, I think the teacher is looking for an expression for the velocity in terms of the height of the tank.

A1V1=A2V2 is just a form of the continuity equation which is a statement of conservation of mass for constant density. Bernoulli's principle is something else.
 
With the SHM problem, how did you do it without knowing the spring constant value?
 
LawrenceC said:
With the SHM problem, how did you do it without knowing the spring constant value?

^This. I was wondering how you could solve without the spring constant.
 
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