ELECTRICAL QUANTITIES

1.Voltage or potential difference
The amount of energy that a generator can transfer to electrons depends on its voltage. This is measured in volts (V).
We use a voltmeter to measure voltage. This object must be connected in parallel to the element that we are checking.


2.Intensity or electric current
It is the charge or number of electrons that flow through the cross-section of a conductor every second. It is measured in amperes or amps (A).
We use an ammeter to measure electric current. It must be connected in series.


3.Electrical resistance
The resistance (R) of a material is equal to the voltage divided by the intensity of the electric current wich travels through the material. This is measured in ohms.


4.Electrical energy
It is is the tension that flows, in a certain time, in an electric current. We can calculate it with this formula: E=VxIxt. It is measured in joules (J).


5.Electric power
It is the amount of energy that it can transform over a certain amount of time. It is measured in watts (W) or kilowatts (kW).             P=VxI       E=Pxt




*In the points 1,2 and 3 we can use the Ohm`s Law to calculate it:    R=V/T