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Simple Explanation of Static Electricity
- Static electricity is the imbalance of electrical charge on an insulated material.
- Static electricity is caused by the transfer of charge (transfer of electrons).
- One method in which electrons can be moved or transferred is by rubbing two insulators together. Rubbing causes friction between the two surfaces increasing the surface contact and allowing more electrons to be transferred. The object which loses electrons becomes positively charged and the one that gains the electrons becomes negatively charged.
Attraction and Repulsion
Key
phrase to remember is:
Opposite charges attract and same charges repel
When a object gets charged it is either positively charged or negatively charged. An object would be positively charged as there are less electrons then protons. Or an object would be negatively charged is there are more electrons then protons. Most object are neutral (they are not charged) this is because they have an equal amount of protons and neutrons. However the number of the electrons can be changed by rubbing to substance together. This only works with insulators (materials that don't conduct electricity).
When two objects that have the same charge (positive and positive or negative and negative) they will repel. However if you get two objects with opposite charges (positive and negative) they will attract.)
Opposite charges attract and same charges repel
When a object gets charged it is either positively charged or negatively charged. An object would be positively charged as there are less electrons then protons. Or an object would be negatively charged is there are more electrons then protons. Most object are neutral (they are not charged) this is because they have an equal amount of protons and neutrons. However the number of the electrons can be changed by rubbing to substance together. This only works with insulators (materials that don't conduct electricity).
When two objects that have the same charge (positive and positive or negative and negative) they will repel. However if you get two objects with opposite charges (positive and negative) they will attract.)
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Induced Charges
When
a balloon is rubbed against clothes the negative electrons from the clothes get
transferred to the balloon making the balloon negatively charged. The balloon
sticks! This is because the negative charge of the balloon repels some of the
electrons in the wall or ceiling away from the surface. This results in an
overall positively charged surface causing the negatively charged balloon to be
attracted.
The separated charges in the wall or ceiling are called induced charges.
The separated charges in the wall or ceiling are called induced charges.
Static Electricity in Action
Rubbing a
polythene strip on wool causes some of the outer electrons in the wool to move
over to the polythene strip. As the polythene gains electrons it becomes
negatively charged. The wool loses electrons and is left with a net positive
charge (more protons to electrons).Only the negative electrons move. The positive
protons remained fixed in the atoms nucleus. Rubbing materials to generate
charge only works for insulated objects.
Dangers of Static Electricity
Filling fuel on a plane can
be very dangerous a lot of friction is applied as fuel goes through the hose.
Meaning hose become charged. This could lead to a spark and then an explosion.
To prevent this from happening ground and earthing is used for wires that
are lined with metal which allows the charge to be conducted away.
Another danger is lightning, which is also caused by static electricity. A cloud becomes charged when water droplets collide and electrons get transferred. This means the cloud becomes negatively charged this makes the positive charge on the floor come up (induced charges). The clouds attracted to ground and charge comes down as lightning. To prevent lightning damaging buildings like skyscraper and churches. They have electricity conductors; they provide protection for building by providing the path of least resistance for the lightning into the earth. It does this by making charge/ lightning travel down the rod and into earth where it will be dispersed safely.
Another danger is lightning, which is also caused by static electricity. A cloud becomes charged when water droplets collide and electrons get transferred. This means the cloud becomes negatively charged this makes the positive charge on the floor come up (induced charges). The clouds attracted to ground and charge comes down as lightning. To prevent lightning damaging buildings like skyscraper and churches. They have electricity conductors; they provide protection for building by providing the path of least resistance for the lightning into the earth. It does this by making charge/ lightning travel down the rod and into earth where it will be dispersed safely.