Electrostatics Part 3

Two charges q1 and q2 are separated by a distance of 30 cm . A third charge q3 initially at ' C ' as shown in the figure, is moved along the circular path of radius 40 cm from C to D . If the difference in potential energy due to movement of q3 from C to D is given by ‌

q3K

4πε0

the value of K is