Electricity

Electricity is produced when there is an imbalance in the movement of positively charged atomic nuclei and negatively charged electrons. The degree of this imbalance is called voltage, and the amount of flow is called current. Also, the difficulty of flow is called resistance.
Current flows from areas of high voltage to areas of low voltage, and from positively charged areas to negatively charged areas.

How is Electricity Generated?

Electrical Generation by Friction
Plastic sheets and the hairs on your head by themselves have no imbalance of positive or negative charges, and are in stable states. However, when the two are rubbed together, the internal charges become unbalanced so that the plastic becomes negatively charged and your hair becomes positively charged. This is called electrical generation by friction. (Static electricity)

Shockwave

Electrical Generation by Chemical Reaction
A zinc plate produces positively charge ions when dissolved in a solution, so that the zinc plate itself becomes negatively charged. The negatively charged electrons travel through a copper wire towards the copper plate. This causes the copper plate to become negatively charged, so that it attracts the positively charged copper ions in the solution. The repetition of this movement of negatively charged electrons forms an electrical current.
The difficulty in dissolving copper ions is due to the fact that copper does not form ions as readily as zinc.
Electrical Generation by Magnetic Movement
Electrical generators convert kinetic energy into electrical energy.
Electrical Generation by Solar Energy
A solar cell converts energy from light into electrical energy.

How are Voltage, Current and Resistance Related?

Think of electricity as a kind of squirt gun.

Now let's connect a battery to a lamp
*The strength of the current is proportional to the voltage, and inversely proportional to resistance. This is called Ohm's Law.
*The electrical energy consumed by a resistor is called electrical power.


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