Resistance is a measure of the opposition to current flow in an electrical circuit. Resistance is measured in ohms, symbolized by the Greek letter omega (Ω). Ohms are named after Georg Simon Ohm (1784-1854), a German physicist who studied the relationship between voltage, current and resistance.

## What is electrical resistance simple words?

Electrical resistance is **opposition to the flow of current in an electric circuit**: resistance converts electrical energy to thermal energy, and in this regard is similar to mechanical friction. Resistances are said to dissipate electrical energy as heat.

## What causes resistance in a circuit?

An electric current flows when electrons move through a conductor, such as a metal wire. **The moving electrons can collide with the ions in the metal**. This makes it more difficult for the current to flow, and causes resistance.

## What is current and resistance?

The flow of electricity through an object, such as a wire, is known as the current (I). The property of a material that limits current flow is known as its resistance (R), the unit of resistance is the **ohm (Ω)**. …

## What is electric resistance and its unit?

Electric resistance has the dimension length squared mass per time cubed electric current squared. The SI derived unit of electric resistance is **the ohm**, which is defined as a volt per ampere. … An abohm is defined as ohm and is energy-equivalent to the unit centimeter per second ().

## What is resistance and its types?

The ratio of the applied voltage to the current through the material is then known as resistance. There may be two types of resistors in general. **Variable Resistors and Set Resistors**. Around resistors. A fixed resistor is one for which its resistance value is defined and in general, can not be varied.

## How is electrical resistance calculated?

**R = V ÷** I Question

What is the resistance of the lamp? To calculate the resistance of an electrical component, an ammeter is used to measure the current and a voltmeter to measure the potential difference. The resistance can then be calculated using Ohm’s Law.

## What are 4 factors that affect resistance?

**There are 4 different factors which affect resistance:**

- The type of material of which the resistor is made.
- The length of the resistor.
- The thickness of the resistor.
- The temperature of the conductor.

## How do you reduce resistance in a circuit?

**Changing the resistance**

- If you increase the number of lamps in a series circuit , there will be less current. …
- You could increase or decrease the resistance in a circuit by using a variable resistor .
- The quantities voltage, current and resistance are linked by the relationship :
- This relationship is called Ohm’s Law.

## What happens if a circuit has no resistance?

If there really were no resistance in the circuit, **the electrons would go around the circuit**, and arrive back at the beginning of the circuit with as much energy as the potential difference (the voltage). That final energy is usually what is dissipated as heat or other types of energy by the circuit.

## How do I measure resistance?

Resistance can be calculated **by measuring the current and voltage using Ohm’s Law**. As a result, a circuit’s resistance value can be determined if the current and voltage measured values are known. Analog multimeters and digital multimeters employ the measurement principle of Ohm’s Law to measure resistance.

## What are the 4 types of resistors?

**Types of Resistors**

- Fixed Value Resistors. These are the predominant type of resistor configuration, and as the name suggests, they have a fixed resistance value. …
- Variable Resistors. …
- Resistor Networks. …
- Carbon Film Resistors. …
- Metal Film Resistors. …
- Wirewound Resistors. …
- Metal Oxide Resistors. …
- Metal Strip Resistors.

## What is resistance and its formula?

Resistance has units of ohms (Ω), related to volts and amperes by **1 Ω = 1 V/A**. There is a voltage or IR drop across a resistor, caused by the current flowing through it, given by V = IR.

## What is called resistance?

Resistance is **a measure of the opposition to current flow in an electrical circuit**. Resistance is measured in ohms, symbolized by the Greek letter omega (Ω). Ohms are named after Georg Simon Ohm (1784-1854), a German physicist who studied the relationship between voltage, current and resistance.

## Why is electrical resistance important?

Resistance is another important property that can be measured in electrical systems. … The same is true with **electricity**. Materials with low resistance let electricity flow easily. Materials with higher resistance require more voltage (EMF) to make the electricity flow.