A point charge q2 = -4.7 μC is fixed at the origin of a co-ordinate system as shown. Another point charge q1 = 0.2 μC is is initially located at point P, a distance d1 = 6.8 cm from the origin along the x-axis.
The charge q2 is now replaced by two charges q3 and q4 which each have a magnitude of -2.35 μC, half of that of q2. The charges are located a distance a = 1.6 cm from the origin along the y-axis as shown. What is ΔPE, the change in potential energy now if charge q1 is moved from point P to point R?

Question

A point charge q2 = -4.7 μC is fixed at the origin of a co-ordinate system as shown. Another point charge q1 = 0.2 μC is is initially located at point P, a distance d1 = 6.8 cm from the origin along the x-axis. 
The charge q2 is now replaced by two charges q3 and q4 which each have a magnitude of -2.35 μC, half of that of q2. The charges are located a distance a = 1.6 cm from the origin along the y-axis as shown. What is ΔPE, the change in potential energy now if charge q1 is moved from point P to point R?