Solving for Velocity: How to Integrate a Complex Function with Constants?

Sewager
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Homework Statement


Integrate
$$v = \sqrt{2g\frac{T-v \pi r^2t}{\pi R^2}}$$

where g,T,r,R are constants

Homework Equations


N/A

The Attempt at a Solution


I tried playing around with the variables, but I am not sure how to integrate this. Just give me a little bit of hint would do. Thanks!
 
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Sewager said:

Homework Statement


Integrate
$$v = \sqrt{2g\frac{T-v \pi r^2t}{\pi R^2}}$$

where g,T,r,R are constants

Homework Equations


N/A

The Attempt at a Solution


I tried playing around with the variables, but I am not sure how to integrate this. Just give me a little bit of hint would do. Thanks!

Integrate what? Are you solving for ##v##as a function of ##r## or ##t## for example, then calculating ##\int v\, dr## or ##\int v\, dt##? Or, are you solving for (say) ##r## as a function of ##v## then computing ##\int r \, dv##? Or are you trying to do something else?
 
Ray Vickson said:
Integrate what? Are you solving for ##v##as a function of ##r## or ##t## for example, then calculating ##\int v\, dr## or ##\int v\, dt##? Or, are you solving for (say) ##r## as a function of ##v## then computing ##\int r \, dv##? Or are you trying to do something else?

I sincerely apologize for my lack of explanations.

v is velocity and t is time. The rest are just constants. I want to integrate velocity vs. time to find the displacement equation
 
Sewager said:
I sincerely apologize for my lack of explanations.

v is velocity and t is time. The rest are just constants. I want to integrate velocity vs. time to find the displacement equation

It will be messy. Just solve for ##v## as a function of ##t## (I.e., ##v = f(t)##) then integrate, or try to. You will get a quadratic equation in ##v##, so there will be two roots (that is, two functions ##v = f_1(t)## or ##v = f_2(t)##) and you will need to figure out which one is the correct root, probably using other information that you have.
 
Ray Vickson said:
It will be messy. Just solve for ##v## as a function of ##t## (I.e., ##v = f(t)##) then integrate, or try to. You will get a quadratic equation in ##v##, so there will be two roots (that is, two functions ##v = f_1(t)## or ##v = f_2(t)##) and you will need to figure out which one is the correct root, probably using other information that you have.
Thank you very much, I think I have a basic understanding now! Very appreciate it!
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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