You may have heard the term “resistance” bandied about in electrical engineering circles and you’re probably wondering just what that means. To understand resistance, you must first know what it is! Resistance is a force that resists an energy change. In simple terms it’s the amount of force that is required to change one state from another. So, if you were to hook a wire onto a metal plate you would find that it had a certain amount of resistance around it.
The actual term resistance comes from the fact that resistors have a certain amount of voltage rating that they can withstand before they melt. A resistive conductor actually has very low resistance, while a conductor with high resistance lets electricity pass through it very quickly. Devices known as conductors actually allow current to pass through them at a very high rate of speed, while at the same time they have a certain amount of resistance built in. Let’s take a look at what exactly they are and how they function!
When working with circuits, resistors are what is used to control the current that flows through a circuit. If current is not allowed to flow through a circuit then it is said to be insulated. This means that the current will not be able to get to a particular area or if a circuit is completely insulated it will fail to conduct electricity. This failure is what causes the circuit to turn off and on, in order to keep electricity moving through the circuit.
There are two types of resistors: electromagnetic and physical. An electromagnetic conductor actually generates its own magnetic field due to its metal coating. Because it has a metal coating, it is said to have a magnetic field which can create a certain amount of flow. With a physical conductor there is no metal coating but it can still produce a potential difference which allows the flow of electricity through the circuit. The potential difference between the two is what is resistance, when a potential difference exists it creates a difference in the electrical and potential energy which makes the flow of the current slow or stop.
If you are going to be using resistance levels as part of your electrical engineering course, you should know what is resistance and what its characteristics are. Resistance is defined as the amount of force that is needed to move an object with a constant velocity. As you may have guessed from the definition of the word, what is the resistance is something that resists a force. There are different kinds of resistances including electromagnetic, physical, and electrical.
Now that you have an understanding of what is resistance let’s take a look at what it is used for in electrical engineering. First it is important to understand why the voltage is measured in volts and not in amperes. The voltage on an electrical circuit is the amount of force that is applied to the circuit only applies that force in one particular cycle. The amount of force can change because of a fluctuation in voltage which is called a voltage fluctuation. It is this potential voltage fluctuation that causes a problem in the electrical circuit and that problem is what is measured in amperes.
Resistance in electronics circuits occurs when there is a difference between the amount of current flowing through the circuit and the amount of force that are resisting the current flow through the resistors. The resistors in electronics circuits work in much the same way as the conductors in traditional electronics design. In order for the resistors to work they need to be able to withstand the force that is being applied to them. As the force changes the amount of resistivity will also change, this is why resistors in electronics circuits are measured in terms of ohm’s.
What is resistance? In order to answer the question ‘what is the resistance?’ you must have an idea of what the working of resistors and electricity is. When you understand how they both work then you will be able to better understand what is resistance and what it is that is causing the potential difference between the amount of electricity flowing through and the amount of force that are resisting the flow of electricity.