The four points shown in the attached picture are near a positively charged rod (shaded circle). Points W and Y are equidistant from the rod, as are points X and Z. A charged particle with mass 3.0 x 10^-8 kg is released from rest at point W and later observed to pass point X.
Suppose the magnitude of the charge is 2 microcoloumbs and that the speed of the particle is 40 m/s as it passes point X. Suppose that a second particle with the same mass as the first but NINE times the CHARGE were released from rest at point W. Would the speed of the second particle as it passes point X be greater than, less than, or equal to the speed of the first particle (with charge of 2 microcoulombs) as it passes point X?
From KE = 1/2 (mv^2), I know that charge is not involved here, and since mass is the same, I believe the speed of the second particle is equal to the speed of the first particle.
However, I'm not sure if I should be using this equation to make a relationship between speed and charge. Other possible equations to use may be: U(potential energy) = qV, and W = -qEd = ΔU
Am I on the right track?