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Electric charge is a fundamental property of matter that allows objects to exert forces on each other. This property is intrinsic to subatomic particles, such as electrons and protons.
- **Electrons** carry a negative electric charge. - **Protons** carry a positive electric charge.
Opposite charges attract each other, while like charges repel. Electric force, related to these charges, is one of the four fundamental forces of nature. Understanding electric charge is crucial for studying various physical phenomena ranging from simple friction to complex electrical circuits.
In any object, the total charge results from the sum of the charges of its particles. If an object has more electrons than protons, it possesses a net negative charge. Conversely, more protons mean a net positive charge.

Electrons and protons possess equal but opposite charges.
- The charge of an electron is \[-1.6 \times 10^{-19} \text{ C}\].- The charge of a proton is \[+1.6 \times 10^{-19} \text{ C}\].
These values are extremely tiny, yet fundamental to the behavior of matter.
When examining any object, the numbers of electrons and protons usually balance out, making the object electrically neutral. However, when there is an imbalance, such as having extra electrons, the object will carry a net negative charge. This difference is crucial in the operation of electrical devices and in phenomena like static electricity.

The unit of electric charge is called the Coulomb (C). One Coulomb is a large amount of charge: it is equivalent to the charge of approximately \[6.242 \times 10^{18}\] electrons or protons.
- Electric charges are typically measured in Coulombs.- Due to the tiny charge of single particles, more practical subdivisions like microcoulombs \[(\mu \text{C})\] and picocoulombs \[(\text{pC})\] are often used.
In our example, the net charge of millions of electrons summed up to be \[-1.6 \times 10^{-13} \text{ C}\]. This illustrates the tiny scales at which these fundamental charges operate, yet they have profound effects on the macroscopic world by influencing currents and voltages, the forces in electrical devices, and even everyday shocks from static electricity.