1. The problem statement, all variables and given/known data A charged particle of mass m and charge q is free to move in the horizontal (x, y) plane, under the influence of the Coulomb potential due to another charge Q that is fixed at the origin. Find the Lagrangian and the differential equations of motion of the mass m, in terms of Cartesian coordinates (x, y). 2. Relevant equations dL/dqi - d/dt * dL/dq'i = 0 L = T - V T = .5mv^2 V= KQq/r 3. The attempt at a solution L = T - V Langrangian = 0.5mx'^2 - KQq/x dL/dx - d/dt * dL/dx' = 0 d/dx(-KQq/x) - d/dt * d/dx'(0.5mv^2)=0 -dV/dt - d/dt(mx')=0 Fx = mx'' Is this the right answer? The question asks for it to be in terms of the cartesian coordinates. However, my answer isn't. Please Help.