Potential of Point Mass: Is V = -k/r + mgz?

Logarythmic
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If I have a point mass that experiences a force

\vec{F}(\vec{r}) = - \frac{k}{r^2} \vec{e_r} -mg \vec{e_z}

is it correct that the potential is

V = - \frac{k}{r} + mgz

??
 
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By the unit vectors used, apparently one uses the cylindric coordinates. Did you check that \vec{F}=-\nabla U using cylindric coordinates ?

Daniel.
 
Yeah that's correct. Can I interpret this as a particle next to a vertical cable or something?
 
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