Electrical resistance is the resistance to the flow of electrical current. This theory was discovered by George Ohm in the 19th century. Resistance is measured in ohms. Electricity is nothing but electrons flowing. In an electrical current, the atoms in the material allow the flow of electrons. If there is poor conductivity it means that the flow of electrons is resisted.
The electrical resistance is actually measured by dividing the voltage by the flow of current in an object. The way the object resists the electrical current depends upon the material.
The flow of current is resisted due to a number of factors:
• The insulation quality
• Impedance of the conductor
• The object density
Electrical resistance is of two types:
1. Direct current ( DC )
2. Alternating current ( AC )
Direct current means that the electric current moves in a unidirectional manner. For example the water that flows out of a garden hose. The water would act like current and the pressure of water will be the voltage. On the other hand the hose would act like a conductor. The hose enables the water to flow in one direction. The wall of the hose provides friction. This then degrades the force of water.
In the case of AC electrical resistance, the only difference in it is that the resistance of electricity flows in different directions.
It is a known fact that any friction creates heat. In the same manner the resistance of electricity will also create heat. If both the friction and resistance are in excess, then the outcome would be dangerous and destructive.
