Think about what happens when you turn on a light; you push the switch. This causes electricity to flow through the wires to the power source, which will convert the energy to light or power.
Let’s start with the energy source. In your circuit, the power sources will provide the voltage and current to energize your device. Then there’s the conductor, which is the wiring in your home. This provides the path that the energy flows through and connects all the other parts of the circuit. Think of this as the electric power flowing through a pipe or a hose.
Then you have the switch, which closes or opens the energy flow of the circuit. Put simply: this is the light switch. This allows the energy to move through so you get power.
Finally, there’s the load. The load is the amount of electrical energy your device needs to work. Think of your TV and your electric bill; that has to do with your load.
Passive Devices or Loads
A passive device is a component that is unable to control the current through another electrical signal. Think of resistors, capacitors, inductors, transformers, and diodes for this.
Active Devices or Power Sources
An active device will let you change the control of the electric flow. If you want to control your circuit like this, you’re using an AC current and a DC current.
How Does it Work?
Let’s discuss how each of them works for better understanding.
Passive Sign Convention
So you have your passive components like your resistors, capacitors, and the ohm which establish a relationship between voltage and current. This helps make up the voltage polarity, which works with the current direction for two-terminal components. This is called the passive sign convention.
When you have a circuit that only contains those ohms in the AC circuit, that is known as a resistive circuit. There will be inductance or capacitance in this kind of circuit since the AC and voltage will both move forward and backward in the direction of the circuit.
The differences in voltage will create electric fields. The higher the voltage, the stronger the field will be. Magnetic fields are created when the currents flow. The more current you have, the stronger the field. Together, these compose the electromagnetic field.
Electric Power in a Circuit
All the power you have in your circuit depends on the principles. This includes ohm and the relationship between voltage, current, and resistance.
Direct Current (DC)
Your DC current is the unidirectional flow of movement that the electrons go through. The intensity of the current can vary over time, but the direction of the current will never change.
Alternating Current (AC)
On the other hand, the alternative current will change direction. The flow of electric charge will sometimes move direction, especially if the sources vary periodically. This is used a lot with the commercial power that we often use.
How is it Generated?
Electric power is generated through a variety of sources. This includes hydroelectric power, electromagnetic power, as well as electric power created through combustion, such as the burning of fossil fuels.
Electric generators supply energy to power any number of devices. While they do supply energy, they don’t create the energy they transmit. Generators receive power from an outside source, whether it’s hydraulic power, or that created from burning fossil fuels. The generator then takes this energy, and through an alternating current, delivers electricity to the device it’s meant to power.
Electric motors leverage the power of electromagnetic fields, whether they use alternating current (AC) or direct current (DC). These motors take in electrical power and convert it into usable, mechanical energy. This allows electric motors to create motion and power any range of appliances.