# 电阻、电感和电容是什么？

## What are resistance, inductance, and capacitance?

Resistance, inductance, and capacitance are the basic components in a circuit, often used to control the behavior of current and voltage. They each represent one of the three fundamental characteristics in a circuit.

First, let's talk about resistance. Resistance is a component in a circuit that obstructs the flow of current. It can be seen as "friction for current," weakening the movement of electrons through the circuit. When electrons pass through resistance, they collide with atoms within the resistance, resulting in a decrease in electron energy level, which slows down the speed of electrons. In simple terms, resistance decreases the current. It is measured in ohms (Ω).

Next is inductance. Inductance is another component in a circuit that stores and releases energy. It can be understood as "inertia for current." When the current passing through an inductance changes, it generates a magnetic field to resist the change in current. This magnetic field stores the energy, which is released when the current stops changing. Inductance exhibits strong resistance to alternating current (current with changes). It is measured in henries (H).

Lastly, there is capacitance. Capacitance is another component in a circuit that stores charge and creates an electric field. It can be seen as a "storage device for current." When charges pass through a capacitor, they accumulate between its metal plates, creating a potential difference between the two plates. When the potential difference reaches a certain value, the capacitor becomes charged and an electric field forms across the capacitor. The capacitor can store these charges and release them when needed. Capacitance is measured in farads (F).

In summary, resistance, inductance, and capacitance serve different functions in a circuit. Resistance is used to regulate current, inductance is used to store and release energy, and capacitance is used to store and release charge. They are important foundational components in a circuit, critical for our understanding and application of circuit behavior.