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Electricity

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Chemistry

Electricity

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Mechanics
Electricity lessons
Electrical components
-Two-terminal electronic components
- Basic electrical components
- Diodes
- What's a resistor ?
- How to determine a resistor value ?
- Resistors effects in circuits
- How to use a resistor ?
- Characteristic curve of a resistor

How to build simple circuits and draw diagrams
- How to build a basic electrical circuit
- How to draw diagrams of electric circuits

The electric current
- Conductors and insulators
- Direction of electric current in a circuit
- The dangers of electricity
- Current intensity - units
how to measure current ?
The Voltage
- The voltage and its units
- How to measure a voltage ?
- Voltage in open and closed circuits
- Rated current and voltage for a lamp
Alternating voltage and current
- Alternating currents effects on led
- What are alternating current and voltage ?
- Periodic alternating voltage and its properties
- Oscilloscope
- Oscillogram
- Frequency
- Measuring RMS voltage with a voltmeter
Serie circuits
- What's a serie circuit ?
- Series circuit properties
- Short circuit in  series circuit
- Current law in series - circuits
- Voltage law in series circuits
Parallel circuits
- What's a parallel circuit ?
- Some parallel circuits properties
- Short circuits in parallel circuits
- Nodes and branches in parallel circuits
- Current laws in parallel circuits
- Voltage laws in parallel circuits
Laws of electricity
- Ohm's law
- Current laws in series circuits
- Voltage laws in series circuits
- Current laws in parallel circuits
- Voltage laws in parallel circuits
Generating electricity
- Voltage for coil wires
What is an alternator ?
- Alternating currents and voltages
- Generating electricity in power plants

Electric power and energy
- Electric power and power rating
- Electric power received by an electrical device
- Electric power consumption by an electrical device
- Relationship between - Electric power and energy


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Laws of electricity

Current laws in series circuits

   
1) The electric current in a series circuit

In a series circuit the current remains unchanged all along the circuit: all electric components receive the same current.

Example:
In the following circuit, the electric current leaves the positive terminal, flows through the bulb, flows through the resistor and then reches the negative terminal
current in a series circuit
All along its path the current remain the same thus we can write:

I1 = I2 = 3



2) Current and number of passive components in a circuit

In series circuit electric, current decreases if a passive component is added:
The more passive components a series circuit includes, the more current decrease.
Inversely, if a passive component is taken off from a series circuit then electric current increases.
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3) Current and order of connection

Whatever is the order of connection in a series circuit, the current doesn't change.

Example:
Current in series circuits and order of connection

These three circuits all include an electric generator, a motor, a bulb, a resistor, an ammeter and five connection wires. The only difference between these circuits is the way components are connected. We can therefore deduce that the current is the same in all circuit:
I1 = I2 = I3
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