Potential Function of a Conservative Force

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SUMMARY

The discussion focuses on finding the potential function associated with the conservative force defined as F = y²(i) + 2xy(j). Participants clarify that the potential function U(x,y) must satisfy the condition ∇U = F, leading to the equations U_x = y² and U_y = 2xy. The correct approach involves integrating the first equation while treating y as a constant, resulting in U(x,y) = xy² + g(y), where g(y) is a function of y. The final potential function is determined by ensuring that the second equation holds true.

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  • Understanding of vector calculus and conservative forces
  • Familiarity with partial derivatives and integration techniques
  • Knowledge of scalar functions and their properties
  • Experience with mathematical notation and equations in physics
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bmb2009
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Homework Statement


Given a conservative force with the Force given as F=y^2(i)+2xy(j), what is the potential function related to it.

Homework Equations



-dU/dx = F

The Attempt at a Solution


I know I have to integrate the components but I don't know how... since the (i) direction was differentiated with respect to x would I just treat the y as constant and say F=xy^2(i)+xy^2(j) + c ?
 
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You're on the right track, but remember that the potential is a scalar function. You've written down a result that is a vector and for some reason called it F. It might help to explicitly write down the components of F in terms of the partial derivatives of U.
 
So would it just be U(x,y)=xy^2 + xy^2 = 2xy^2 + c because it's a scalar?
 
bmb2009 said:
So would it just be U(x,y)=xy^2 + xy^2 = 2xy^2 + c because it's a scalar?

Close, but no. Remember, you are looking for a scalar function ##U(x,y)## such that ##\nabla U = \vec F##. So you need ##U_x = y^2## and ##U_y = 2xy##. Start by taking the anti-partial derivative of the first one with respect to ##x## by holding ##y## constant, as you asked in your original post. Don't forget when you do that your "constant" of integration will be a function of ##y##. Them make the second equation work.
 

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