How Can You Determine the Potential Function of a Conservative Force?

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To determine if a force field F is conservative, it is essential to show that the curl of F is zero (rot F = 0) or that the force can be expressed as the gradient of a potential function U (grad U = F). The force field is given as F = r/r, where r is the position vector. To find the potential function U, one must integrate the components of F, ensuring that the integration constants are functions of the other variables. This highlights the importance of understanding multi-variable calculus in the context of conservative forces. The discussion emphasizes the relationship between force fields and potential functions in physics.
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to know that a F is a conservative i need to prove that
rot \vec{F}=0
or that grad U=\vec{F}
<br /> \vec{F}=\frac{\vec{r}}{r}<br />

how to know U (potential of F)
??
 
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slonopotam said:
to know that a F is a conservative i need to prove that
rot \vec{F}=0
or that grad U=\vec{F}
<br /> \vec{F}=\frac{\vec{r}}{r}<br />

how to know U (potential of F)
??

Well, if \textbf{F}=\mathbf{\nabla}U=\partial_x U \hat{x}+\partial_y U \hat{y}+\partial_z U \hat{z}=F_x\hat{x}+F_y\hat{y}+F_z\hat{z} (are you familiar with this notation?), then U=\int F_x dx, U=\int F_y dy and U=\int F_z dz must all be true. An important note is that in multi-variable calculus, the 'constants' of integration are only constant with respect to the integration variable, so, for example \int3x^2 dx=x^3+f(y,z)
 
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