A point object with a positive charge +Q is placed on the x-axis at x =-d. A second point object of unknown charge is placed at an unknown location on either the x-axis or the y-axis." The potential energy associated with the charges is U = +2k d The potential at the origin due to the charges is V = + x=-d The net electric field at the origin due to the two charges points in the negative x direction. Assume the electric potential is zero at infinity. Before solving for the unknown charge and location answer these questions. 1) What is the sign of the unknown charge? positive [ I negative [ ] can not be determined How do you know? (ii) Where is the unknown charge located? i I positive x-axis [ I negative x-axis [ ) positive y-axis ( ] negative y-axis How do you know? Determine the value (sign and magnitude) of the unknown charge and state its location. What is the magnitude of the electric field at the origin?