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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


Series circuits

Series circuit properties

1) Order of electric components

In a series circuit if we permute two different bulbs then each bulb maintains its brightness.

More generally:
In a series circuit, modifying the order of connection does not affect the way electric components operate.

2) Number of passive components

If we add a second bulb in a circuit including a bulb and a battery then the brightness decreases.
The brightness decreases even more if we add a third.
The result would be the same by adding a motor or a resistor instead of a bulb.

The more a series circuit includes passive components,  the more its bulbs get brighter.


3) Burnt out bulb or unscrewed bulb

If a bulb is burnt out or is unscrewed in a series circuit including multiple bulbs then all bulbs stop to shine.

If a bulb burns out then the filament is broken and when a lamp is unscrewed there is no more contact between the bulb and the socket.
In both cases the circuit is open and the electric current can not flow.

Conclusion: In a series circuit if a bulb is burned out or unscrewed other passive components do not work anymore.