Figure (a) shows two charged particles fixed in place on an x axis with separation L. The ratio q1/q2 of their charge magnitudes is 4.00. Figure (b) shows the x component Enet,x of their net electric field along the x axis just to the right of particle 2. The x axis scale is set by xs = 30.0 cm.

(a) At what value of x > 0 is Enet,x maximum?

(b) If particle 2 has charge – q2 = – 3e, what is the value of that maximum?