Two positive charges, each , and a negative charge, , are fixed at the vertices of an equilateral triangle of side 13.0 cm. We have to find the electrical force on the negative charge.

Solution:             Click For PDF Version

Because of the symmetry the vector sum of the y-components of the forces on the charge, , due to charges will cancel and the net force on it will be the sum of the x-components. The force on the negative charge, therefore, will be along the x-axis and its magnitude will be

Or