Need desperate help on fluid dynamics

[Cyrus]

Looking at your data, your equation matches very well to what vanesche gave.

Look over your work with more care.

 

[gtabmx]

Wait, which equation, the one provided on the site or the one i have just posted?

 

[Cyrus]

The one on the site. I don't know what that mess you posted is, sorry.

 

[gtabmx]

So you manipulated the equation ont he site into something useful where velocity is not included or did you use the equation as is?

 

[gtabmx]

How can that be, I plug 25seconds into that equationa nd get -2.3meters?

 

[Cyrus]

what do you mean velocity, where do you see velocity anywhere?

 

[gtabmx]

"The symbol u stands for the fluid velocity"

on site

 

[Cyrus]

Yes, and where do you see it in the final equation?

Think about conservation of energy.

 

[gtabmx]

Nowhere, ok so your are using the last equation, I thought you rederived another equation from Bernouilli's equation. Yes, I am using that last equation and it does not fit, perhaps my values for lambda are worng. I solved for them and got around 4.0E-3. Correct?

 

[Cyrus]

I got your graph to match, you better redo those calculations boy, or I am going to smack you!

 

[gtabmx]

OKOKOK i will gimme a sec

 

[gtabmx]

OK, i get lambda is either equal to 9.251E-3 or 3.526E-3 with inconsistent units, correct?

 

[Cyrus]

Nope. Check your work some more. You are close though.

 

[gtabmx]

Oh god, look I know you are trying to do this for my own good but I looked over it and found nothing wrong and I have fired up maple to triple check and here.

{x = 0.003525914211}, {x = 0.009251617087}

 

[Cyrus]

Can you write me your equation your using to solve for lambda?

It might be that its rounding off, but I want to be sure its not what I think it might be.

 

[gtabmx]

0.0251 = 3062.500000 x - 39.13118960 x + 0.125

0.0251 = 3062.500000 x - 39.13118960 x + 0.125

"->"
{x = 0.003525914211}, {x = 0.009251617087}

 

[Cyrus]

No, this is not correct.

Where did you get these numbers?

Intercept is ok, but the rest are wrong.

Where did this come from?

0.0251?
3062.500000 ??
39.13118960 ??

 

[gtabmx]

I used the equation and i plugged 25s into time and the corresponding height 0.0251m from my results and i simplified.

 

[Cyrus]

Ah, this is fine.

BUTTT, you should use data points as far as possible, i.e. use 35.

You will find that you get:

0.0035822
0.00551068

 

[gtabmx]

ok, so wat a couple of decmals so, wat are the units of lumbda?

and now wat? there must be a way to find the values before even doing the experiment?

 

[Cyrus]

You tell me.

Not a couple of decimals, a factor of 2.

 

[gtabmx]

It was a joke, i understand.

 

[gtabmx]

No units, makes me feel better i think

 

[gtabmx]

So now i know lambda has no units and u must do the experient to find it, that's not taht good since its not a general formula yet

 

[gtabmx]

Wait, lambda is not consistent, it has not units is in first term and units in second

 

[Cyrus]

Are you sure?

 

[gtabmx]

m = m/s^2 * ?^2 * s^2 is first term so m = m * ? no units
m = m^(1/2)/s * ? * m^(1/2) * s is second term so m = ? units

 

[Cyrus]

What is this?

Do a proper dimensional analysis, and take your time.

 

[gtabmx]

I DID IT 5 TIMES adn I was about to take a picture of it with my phone until i found out the qualiy sucks

 

[Cyrus]

Then do it a 6th time, but TAKE YOUR TIME!

Show me some work, try to make it cleaner.

 

[gtabmx]

same thing again, look, why can't u understand that i get the same thing?

 

[gtabmx]

WAIT 1/m 1/m no, oh now I'm even more confused

 

[Cyrus]

Here:

$$\frac{m}{s^2} s^2 * \lambda = m$$

Lambda is units of meter

$$\sqrt{ \frac{m}{s^2} {m}} * s *\lambda = m$$

lambda is in units of meter, and it better be.

come on, this is algebra 1. I warned you to TAKE YOUR TIME.

 

[gtabmx]

You know I have a feeling that's not right look at the final equations, each term has to be in meters after all the steps are carried out now the first temr is Y^2 times gravity times time squared which is m = Y^2 * m*s(-2) * s^2 so then s^(-2) outs s^2 and you have m = Y^2 * m no?

 

[gtabmx]

ohh
wait
wait wait

heres my deal, i made a stupid mistake probably due to the fact that I've been up till 2AM adn woke up at 6 for the past 3 days so I'm sorry

also, i get consistent, but NO UNITSyup sextuple checked no units as simplified its m = m * y^2 - m * y + m

u even proved it yourself

so your second tex simplifies to

m lambda = m