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Science class

Chemistry

Electricity

Optics

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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Parallel circuits

Parallel circuit properties

   
1) Number of passive components


We first make a parallel circuit including a battery, two lamps and then we add a third lamp connected in parallel:
Parallel circuit with two and three lamps




The brightness of L1 and L2 lamps stays the same despite the addition of a third lamp.

In a parallel circuit, the brightness of a lamp is the same whatever is the number of passive components in this circuit.

2) Burnt out bulb or unscrewed bulb

We make the following parallel circuit in order to observe what happens when unscrewing a lamp:
Parallel circuit with three lamps


Observation: si l'une des lampes est dévissé les autres lampes continuer à briller de la même manière. Nous obtenons le même résultat si la lampe est grillée.

Interprétation: Si une lampe est dévissée les autres continuer à briller car elles sont dans d'autres boucles qui restent fermées.

Conclusion: Dans un circuit parallèle, si la lampe est grillée ou est dévissé les autres composants passifs continuer à fonctionner de façon indépendante.



 


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