2. ELECTRICAL QUANTITIES

2.1 Voltage or potencial difference.

The amount of energy that a generator can transfer to electrons depends on its voltage or electric tension. This measured in volts

If we to measure voltage, we can a voltmeter. This device has tow wires that must be connected in parallel to the element that we are cheking

2.2 Measuring electrical current

Electrical current is the charge or number of electrons that flow through the cross-section of a conductor every second. We can express this mathematically as-folows.

we can use an ammeter to measure electric current. This instrument is connected in series, so that all the electrons must pass through it.

2.3 Electrical resistance: ohm's law.

The resistance of a material is equal to the voltage divided by the intensity of the electric current which travels through the materials. This ratio, which is called Ohm's law, can be expressed as follows.

                                                      R=V/I

2.4 Electrial energy and power.

Electrical energy.

If an electric current flows at a particular tension for a certain amount of time, we can calculate the energy that is consumed. E=V x I x t

Electrical power.

If an electric current flows at a particular tension, we can calculate the power that is consumed. 

                                                   P=V x I

we simply multiply the power in kilowatts by the amount of time in hours.