Final answer:
There are only two types of electric charge: positive and negative. Like charges repel each other, while unlike charges attract. Charge is measured in coulombs, and the force between charges follows an inverse square law.
Step-by-step explanation:
Types of Electric Charges
There are two fundamental types of electric charge: positive and negative. Objects with like charges, meaning either positive with positive or negative with negative, will repel each other. Conversely, objects with unlike charges will attract each other. This is a foundational concept in physics, illustrating how charged objects interact. For example, when glass is rubbed with silk, glass acquires a positive charge, while silk gains a negative charge. The force that acts between these charges decreases with the square of the distance between them, which is an essential aspect of Coulomb's law.
Materials can be charged in different ways, such as by contact, by conduction, or by induction. When two objects with the same type of charge come into close contact, they repel due to the force that exists between similar charges. If they are of opposite types, they attract, as observed with the glass and silk example. The picture below illustrates a neutral object with balanced positive and negative charges, a positively charged object with an excess of positive charge, and a negatively charged object with an excess of negative charge.
The most common carriers of positive and negative charges in nature are protons and electrons, respectively. The unit used to measure electric charge is the coulomb (C), named after physicist Charles-Augustin de Coulomb.