Two charges q and Q are fixed in place along the x axis. Q = +2.4 nC is at x = -3.5 m and unknown charge q is located at x = 1.3 m. a) It is found that the net electric field is zero at x = -0.30 m. What is the magnitude and sign of charge q? b) An electron is fired at x = 2.0 m away from the two charges q and Q. What initial speed does the electron need to stop and turn around at x = 10 m?

Two charges q and Q are fixed in place along the x axis. Q = +2.4 nC is at x = -3.5 m and unknown charge q is located at x = 1.3 m. a) It is found that the net electric field is zero at x = -0.30 m. What is the magnitude and sign of charge q? b) An electron is fired at x = 2.0 m away from the two charges q and Q. What initial speed does the electron need to stop and turn around at x = 10 m?