1. The problem statement, all variables and given/known data A point charge Q resides at the origin. A partical of mass 0.001kg carries a charge of 6 microC. The particle is released from rest at x = 3m. Its kinetic energy as it passes x = 0.5m is 0.4J. The coulomb constant is 8.99x10^9Nm^2/C^2. Find the charge Q. Answer in microC. 2. Relevant equations I use kqQd = -k 3. The attempt at a solution (8.99x10^9Nm^2/C^2)(6 microC)Q[(1/0.5)-(1/3]) = -0.4 Q=-4.44x10^-12 I don't know what I did wrong and is kinda confused. Can anyone help???