What is resistance in electricity

What is Resistance in Electricity?

Any Element or Material have there owned Resistance property. The resistance is the Electrical component that can be used in different electric circuits or electronic gadgets. 

The main task of resistance

The main task of the resistance can be to oppose the follow of free electron on the material when the voltage is applied to the resistance or resistance materials.

working principle 

When we applied electric force to resistive material the free electrons of the material is moving or acceleration, that king of moving free electrons through the resistive material collide electrons with each other, and found opposes the moving of free electrons, This king of restriction or opposition of electrons is can be said in the electronic field is resistance, and the heat is produced inside the resistive component when free electrons collide between one electron to other electrons.

SI unit of Resistance

The SI unit of Resistance is “ohm” and is denoted by the Greet letter Ω.

What Material use in Resistance?

Mostly Metallic material used to performing a task and known as conductors and it is passive device

  1. Silver and Gold:                     

Silver and Gold is excellently good conductors or material but it can not be used because this material have more Expensive as compare to other materials.

     2. Aluminium.

Aluminium is a good conductor to flow of free electrons . and can be used commonly because conveniently available in the relevant market and have low cost or less expensive.

     3. Copper.

Copper is another very good conductive material and has commonly used to perform a task, Copper is a better or good conductor as compare to aluminium but it is more expensive then aluminium and copper are widely used in electric and electronic circuits in different ways.

      4. Simiconductor

This kind of conductor is mostly used in electronic devices or electronic components like Transistor, diode, rectifier, resistance, Transducers,vdf, etc. This mostly uses of semiconductor material and have especially made the manufacturing process to make these semiconductor materials, the name is Germanium and Silicone, are two commonly used materials to make components. 

Measuring the resistance value.

There are two different ways to find out resistance value

  1. Through the multimeter
  2. through the colour-coding system.

Through the Multimeter.

Performing measuring task with the help of a Multimeter or ohmmeter.


Turn off the power supply, make sure the multimeter selective probe is ohm position and two leads of multimeter are connected to resistor endpoints of the resistor so the value can be display in the multimeter.

Performing measuring tasks with the help of the color-coding system.


The second method to be found in the measured the ohmic value is color-coding system, the color-coding system is to be found in resistor material to be print out in resistive components. and denoted by the band, there is 4 band and 5  and 6 band.can be shown in fig…

Resistor color coding



Colour Digit Multiplier Tolerance
Black 0 1  
Brown 1 10 ± 1%
Red 2 100 ± 2%
Orange 3 1,000  
Yellow 4 10,000  
Green 5 100,000 ± 0.5%
Blue 6 1,000,000 ± 0.25%
Violet 7 10,000,000 ± 0.1%
Grey 8   ± 0.05%
White 9    
Gold   0.1 ± 5%
Silver   0.01 ± 10%
None     ± 20%

Types of Resistance.

  1. fixed.
  2. variable.
  3. wire-wound.
  4. carbon composition.
  5. carbon film.
  6. metal film.
  7. surface mount.


fixed resistance can be used commonly in electronic gadgets or circuits and its value can not change will say other points of view that its fixed value. 


that kind of resistance can be used in a different way when need not fixed value and can use the different values performing that kind of resistors and value is changeable.


that kind of resistor can be used when high power used in the circuit.

Series and parallel connection of the resistor.


Series circuit.

The total resistance in a combination with one or more resistor is connected in series.


Req = R + R + R

series resistance circuit





parallel circuit

That kind of combination resistor can be denoted and say parallel circuit as showing in fig…


Req = 1/R1 + 1/R2 + 1/R3

Resistace in parallel








measuring resistance 

There is another way to calculated or measure the ohmic value is given by the ohm law formulas



R= resistance.

V= voltage.

I= current.

unit of Resistance

Table of resistance value and conversion.

Name Symbol Conversion
mili-ohm m Ω 1mΩ = 10-3Ω
ohm Ω
kilo-ohm K Ω 1kΩ = 103Ω
mega-ohm 1MΩ = 106Ω


  1. This is very less expensive.
  2. Easy to replacement.
  3. It is very small or less weight.


  1. The high resistance will oppose big value of electric current and hence the big value of energy is wasted in the form of heat. 

Related Articles

Types of resistors

Capacitor working principle

Electrical Engineering








what is Resistance in Electrical
Article Name
what is Resistance in Electrical
The main task of the resistance can be to oppose the follow of free electron on the material when the voltage is applied to the resistance or resistance materials.
Publisher Name
Ghulam Hyder
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