Three charged spheres with q1 = -9 μC, q2 = 4 μC, and q3 = -7 μC charges are located at distances d1 = 120cm, and d2 = 80 cm.
![240_Three charged spheres.png](https://secure.tutorsglobe.com/CMSImages/240_Three%20charged%20spheres.png)
(a) What is the magnitude and direction of the net electrostatic field at charge q1?
(b) What is the magnitude and direction of the net electrostatic force on charge q1?
(c) How much energy is required to assemble these three charges?