# What is resistor and its uses?

A

**resistor**is an electrical component that limits or regulates**the**flow of electrical current in an electronic circuit.**Resistors**can also be used to provide a specific voltage for an active device such as a transistor.A.

### What is a resistor and how does it work?

Devices called

**resistors**let us introduce precisely controlled amounts of**resistance**into electrical circuits. Photo: Four typical**resistors**sitting side by side in an electronic circuit. A**resistor works**by converting electrical energy into heat, which is dissipated into the air.#### How do you read the value of a resistor?

**Steps**- Position the resistor with the gold or silver color band to the right..
- Read the color sequence that must be decoded to determine resistance.
- Determine the coded number for the resistive value.
- Determine the tolerance of the resistor.
- Determine the decoded number for the resistive value.

#### Is a light bulb a type of resistor?

The reason a**light bulb**glows is that electricity is forced through tungsten, which is a**resistor**. The energy is released as**light**and heat. A conductor is the opposite of a**resistor**. Electricity travels easily and efficiently through a conductor, with almost no other energy released as it passes.#### What is a capacitor and what does it do?

A**capacitor**(originally known as a condenser) is a passive two-terminal electrical component used to store energy electrostatically in an electric field. Unlike a resistor, a**capacitor does**not dissipate energy. Instead, a**capacitor**stores energy in the form of an electrostatic field between its plates.

B.

### What is the importance of a resistor?

The main function of

**resistors**in a circuit is to control the flow of current to other components. Take an LED (light) for example. If too much current flows through an LED it is destroyed. So a**resistor**is used to limit the current.#### How do we measure resistance?

Electrical**resistance**is**measured**by either of two methods: constant current or constant voltage. The constant current technique sources a known current through an unknown**resistance**and the resulting voltage is**measured**. This technique is generally used for**resistance**values below 200M ohms.#### Why capacitors are used?

Power conditioning. Reservoir**capacitors**are**used**in power supplies where they smooth the output of a full or half wave rectifier. They can also be**used**in charge pump circuits as the energy storage element in the generation of higher voltages than the input voltage.#### What is a transistor and what does it do?

A**transistor**is a miniature electronic component that can**do**two different jobs. It can work either as an amplifier or a switch:**Transistors**can also work as switches. A tiny electric current flowing through one part of a**transistor**can make a much bigger current flow through another part of it.

C.

### Do resistors lower voltage?

In short:

**Resistors**limit the flow of electrons, reducing current.**Voltage**comes about by the potential energy difference across the**resistor**. The mathematical answer is that a**resistor**is a two-terminal electric device which obeys, or you could say enforces, Ohm's law: V=IR.#### Can you use a resistor to reduce voltage?

The**voltage**dropped by a**resistor**is given by Ohm's Law: V = I R. So if you know exactly how much current your device**will**draw, you**could**choose a**resistor to drop**exactly 7.5 V, and leave 4.5 V for your device, when that current is run through it.#### What happens to current If you add resistors?

In a series circuit,**adding**more**resistors**increases total resistance and thus lowers**current**. But the opposite is true in a parallel circuit because**adding**more**resistors**in parallel creates more choices and lowers total resistance. If the same battery is connected to the**resistors**,**current**will increase.#### Is potential difference and voltage drop the same thing?

**Voltage**is the**potential difference**between the source & any point in the circuit.**Voltage drop**means, amount of**voltage**by which**voltage**across load resistor is less then the source**voltage**.**Voltage**across the resistor =**Potential difference**between the two terminal of the resistor, which here is V(load).

Updated: 29th September 2018