Answer:
Step-by-step explanation:
q1 = - 5.1 micro coulomb
q2 = 5.1 micro coulomb
q3 = 5.1 micro coulomb
d = 2.2 cm
Let these charges are placed at A, B and C of the vertices of an equilaterla triangle
Force on A:






The net force acting on q1 is given by


F1 = 837.71 N
Force on B:






The net force acting on q1 is given by


F2 = 483.65 N
Force on C:






The net force acting on q1 is given by


F3 = 483.65 N