4.TYPES OF CURRENT

4.1.DIRECT CURRENT:
Between the terminals of a battery,theree is a continuous,stable flow of energy.If we use a voltemeter to measure the current in a car battery,the result will always be 12 volts.This is called direct current.In the same way,if we connect a light bulb to a battery,the electrons always flow in the same direction with the same current.

4.2.ALTERNATING CURRENT:
If we measured the voltaje of an electrical socket,the results could be represented in a graph like the one below:

• The current begins at 0V and increases to 325V.
• The current decreases from 325V to 0V.
• The current becomes negative and decreases to -325V.
• The current increases to 0V.

The variation of any electrical parameter over a period of time is an electric signal.
The tensión or voltage of domestic electricity is an alternating signal becouse it alternates between positive and negative values.Its waveform is also sinusoidal,with a smooth,regular shape.