Two point charges are fixed on the x-axis: +4μC at x=0m and −3μC at x=0.30m. Point P lies on the axis at x=0.20m.
a. (a) Find the magnitude and direction of the net electric field at P due to the two fixed charges.
b. (b) Hence calculate the magnitude and direction of the force that would act on a +2μC test charge placed at P.