Electric Charges and Fields

1.1 Electric Charge

Electric charge is a fundamental property of matter. There are two types:

• Positive charge (e.g., protons)
• Negative charge (e.g., electrons)

Quantisation of charge:

$$q = ne, \quad n \in \mathbb{Z}$$

where $e = 1.6 \times 10^{-19}\,\text{C}$ is the elementary charge.

Conservation of charge: The total charge in an isolated system remains constant.