A group of students are conducting an investigation about charging through the process of friction. The students rub two neutral materials together, and there is a transfer of electrical charge from one material to the other. What is the net electrical charge of the objects together? and Which of the following interaction between two charges will lead to an ATTRACTIVE Fele?

In charging by friction, one object is rubbed against another object; one of the two objects has more tendency to acquire electrons than the other one, so it attracts electrons from the the first object.

As a result, at the end of the process, one object will have an excess of electrons (negative charge) while the other object will have a lack of electrons (so, net positive charge).

The direction of the electrostatic force between two charged objects is as follows:

- The force is attractive if the two objects have opposite charges (+- or -+)

- The force is repulsive if the two objects have same sign charge (++ or --)

Therefore in this case, since the two objects are left with opposite charge, they will attract each other.

Moreover, the law of conservation of charge tells us that the negative charge has been transferred from an object to the other, however, there is no exchange of charge between the two objects and the surrounding; therefore, the total net charge of the two objects will remain the same as the beginning, therefore zero.