Electrical circuit question?
Shock report reveals all!
What Exactly IS An Electrical Circuit?
We’re certainly glad you asked, because, if you hadn’t, there’d be no need for me, your friendly, and, hopefully, helpful guide to what exactly an electrical circuit is. You might say this is something like “Electrical Circuits For Dummies” or something of that ilk. We’re all familiar with the term “electrical circuit”, but, if you’re anything like us, chances are if somebody asked you to describe what one was, you may have a hard time actually putting it into words. We hope this explanation takes care of that problem for you, as it did us.
So, without further ado, we give you (drum roll, please, Ringo!), your very own…
An electrical circuit is the continuous path of electron flow from a voltage source, such as a battery or photovoltaic module, through a conductor (wire) to a load (in the example we’re using, a light bulb) and back to the source. The derivation of the term says it all. To be a circuit, it has to “go around”. Moving electrons do the work in what’s called “electricity”. But, they aren’t moving from point A (a battery or utility power station) to point B (your loads (i.e. your household appliances, electrical gadgets, etc.)) and stopping or being “used up”. They’re moving in a circle through the source, to the load, and back again to where they started. A simple electrical circuit is shown below as a schematic and a diagram. This example shows a single voltage source, a 12-volt battery, wired to a single load, a 12-volt, 24-watt light bulb, with a switch to turn the light on and off.
Sgt Pepper’s Lonely "Hearts" Club Band
OK, we might be stretching things a bit using the title of The Beatles greatest album as a subheading, but we think the stretch is worth it! An excellent analogy for a circuit is blood flow in the body. The heart is like a battery or generator, and blood is like electrons being pumped around a complete circuit, keeping the body cleansed and oxygenated on the way.
The (Inner) Light
The switch controls the continuity of current flow. If the switch is turned off (an open circuit), the wire between the source and the load (in this case, the light bulb) is disconnected, and the light will be off. If the switch is turned on (a closed circuit), the wire between source and load is connected, and, provided there is energy stored in the battery, the bulb will light up.
Here’s Our Old Friend, The Water Pump Again
An electrical system can he compared to a water pumping system. A pump lifts two gallons of water per minute from a lower tank to an upper tank, increasing its height and pressure by 12 feet, the distance between the two tanks. The pressure created by the 12-foot height of the upper tank is like the 12-volt electrical pressure in the battery. The water falls at two gallons per minute from the upper rank and turns a water wheel, losing its height and pressure as it returns to the lower tank. The filling of water at two gallons per minute to turn the water wheel is like the two amp flow of electrons that powers the light and returns to the battery.
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