In an equilateral triangleABC ,charges q,q and -q are at three vertices A,B,and C respectively.find out forces on each charge due to other two charges and also find out sum of all the three resultant forces experienced by the each of three charges?

Force applied by q on q is f=kq^2/ASame will be the force on q by q now force on -q by q f=-Kq^2/A There will be 2 forces apllying on -q at angle 60° from each other therefore resultant force on -q will be (f)^1/3 direction will be towards triangle i.e f=(-kq^2/A)^1/3 .Now there will be two equal forces acting on q with angle 120° with each other the resultant wil be f only i.e resultant f will be f=k q^2/A