Two identical metal objects are mounted on insulating stands. Describe how you could place charges of opposite sign but exactly equal magnitude on the two objects.

This is a phenomenon in Physics in which there is a finite transfer of charged particles from one object to another when there is excess charge pile up or an imbalance of charge at some place. As an example, if two insulating objects are vigorously rubbed they can acquire equal and opposite charges.

The objects 1 and 2 is designated as 1 to the left and 2 to the right for orientation. They are neutral initially and they are slowly brought together for contact.

After they are in contact, another positively charged rod is brought close to the object 1 from the left side. This action will cause pulling of electrons in object 1.

Now, move the object 2 away without disturbing the contact of the object 1 and the other object. This makes, the object 1 negatively charged and the object 2 positively charged and the magnitude of the charge is equal in both.