Voltage - part [1]

What is voltage?

Definition:

Voltage, electric potential, electric pressure or electric tension is the difference in electric potential between two points, In other words, Voltage is a force provided by a power source that pushes electrons through a conducting circuit enabling them to apply this energy in another form (illuminating a light, moving motor, etc...).

We can use Voltameter to measure the voltage (or potential difference) between two points in a system.

Here`s an example of Voltage in a direct current (dc) circuit:

1. in this circuit, if we open the switch (switch turned OFF) the circuit will be no longer close so no current flows and the lamp won't illuminate.

1. in otherwise, If we close that switch (switch turned ON) the circuit will be a closed circuit 

•  which allows voltage to push electrons (current ) through this closed loop from the negative terminal of the battery to the positive terminal of it

• When electrons reach the lamp (what we call current) the lamp convert that charge into a light which will make it glow.

• then electrons back again to the source (battery)

so if electrons that come out from a battery return back again to it (why the battery have a limit time?)

-simply we need to know the difference between current and voltage, then it will be easy to understand why we are doing that.(we just said that voltage is a force or pressure we need to apply to move electrons through our circuit and that is simply the answer, the voltage is an energy we are saving in a power source, so moving electrons in our circuit uses that force which is depending on the load(R).-that force has a limit which indicates the limit of our source so 9v batteries have more time than 11v batteries [in case your load is the same].