Two positive charges, one of magntude Q and the other of magnitude 2Q, and one negative charge of magnitude -Q are placed on a straight line. The -Q charge is in the middle with Q to its left and 2Q to its right. The distance between the charge on the left and the charge in the middle is d, while that between the charge in the middle and the charge on the right is 2d.
A) Find both the magnitude and direction of the net force on the positive charge on the left.
B) Find both the magnitude and direction of the net force on the negative charge in the middle.