What is defference betwen coil and resistor?

The resistor is a chunk of material in which the charges, flowing as a current, tend to bump against "obstacles" (the crystal lattice) devolving the energy they had that will appear as heat or light. We have a definite "resistance" to the passage of current in a resistor and that's it!

The coil (although it can have a certain resistor-like resistance) produces a Magnetic Field that will "react" to the passage of current through it opposing the changes in current. To have an idea have a look at Faraday-Lenz law and the fact that the magnetic field induced inside the coil will tend to oppose the increase of current and try to sustain the current when it decreases!!!

A coil and a resistor are both electronic components used in circuits, but they serve different purposes and exhibit different characteristics.

1. Resistor:

• A resistor is a passive two-terminal electrical component that resists the flow of electric current.
• It is primarily used to control the flow of current in a circuit, limiting the amount of current that passes through it.
• Resistors are commonly used to adjust signal levels, divide voltages, bias active elements, terminate transmission lines, and provide load resistance in electrical circuits.
• Resistors dissipate electrical energy in the form of heat, depending on the current flowing through them and their resistance value.
• Resistors are characterized by their resistance value, measured in ohms (Ω).

2. Coil (Inductor):

• A coil, also known as an inductor, is a passive electronic component that stores electrical energy in a magnetic field when current flows through it.
• It consists of a coil of wire wound around a core, often made of ferromagnetic materials like iron or ferrite.
• Inductors resist changes in current flow, causing the current to lag behind the voltage in an AC circuit and oppose sudden changes in current in a DC circuit.
• Inductors are used in various applications, including filtering signals, tuning radio circuits, energy storage in power supplies, and creating magnetic fields in motors and transformers.
• The unit of inductance is the henry (H), and inductors are characterized by their inductance value, which determines their ability to store energy in the magnetic field.

In summary, while both resistors and coils are electronic components used in circuits, resistors primarily control current flow by resisting it, dissipating energy as heat, whereas coils (inductors) store energy in a magnetic field and resist changes in current flow.