Determining the path of a particle in a field

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fishspawned
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Homework Statement
using integration to determine paths of travel
Relevant Equations
F(x,y) = x+y [for example]
This is not a specific homework question, but more of a general query.

If provided with a simple vector field indicating forces (for example, an electrical field), can you use integration to determine the path of a particle placed in that field, if also provided with some initial conditions? Let's say this is a simple 2D plane where the field follows something fairly simple, like F(x,y) = x+ y. Can this be done? Can anyone point me in the right direction to learn more about this?

Consider this as an attempt to change a grid of vectors into a set of field lines that, at the same time, show the path of a set particles within that field
 
on Phys.org
Your field, F= x+ y, is NOT a "vector field" because x+ y is not a vector!

If you had something like F= xi+ yj then, since Force= mass* acceleration, the acceleration would be [tex]\frac{d^2x}{dt^2}= x[/tex] and [tex]\frac{d^2y}{dt^2}= y[/tex]. The "characteristic equation" of both is [tex]r^2= 1[/tex] and So that [tex]x(t)= Ae^t+ Be^{-t}[/tex] and [tex]y(t)= Ce^t+ De^{-t}[/tex].

Another possibility is that F is not a force vector but a potential energy field. In that case, the force is given by the negative of the gradient of the potential energy field. With potential energy x+ y, the force vector is [tex]-i- j[/tex]. Then [tex]\frac{d^2x}{dt^2}= -1[tex]and [tex]\frac{d^2y}{dt^2}= -1[tex]so that, integrating twice, [tex]x(t)= -\frac{t^2}{2}+ At+ B[/tex] and [tex]y(t)= -\frac{t^2}{2}+ Ct+ D[/tex].[/tex][/tex][/tex][/tex]