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Simple Explanation of Static Electricity
- Static electricity is caused by a 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, allowing more electrons to be transferred.
Attraction and Repulsion
Opposite charges attract and same charges repel.
When a object gets charged it is either positively charged or negatively charged.
Positively charged if there are less electrons then protons. Negatively charged if there are more electrons then protons.
Most object are neutral (not charged), because they have an equal amount of protons and neutrons.
The object which loses electrons becomes positively charged and the one that gains the electrons becomes negatively charged.
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.)
When a object gets charged it is either positively charged or negatively charged.
Positively charged if there are less electrons then protons. Negatively charged if there are more electrons then protons.
Most object are neutral (not charged), because they have an equal amount of protons and neutrons.
The object which loses electrons becomes positively charged and the one that gains the electrons becomes negatively charged.
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.)
Induced Charges
When you rub a balloon against your clothes, you're adding negative electrons to the clothes (a negative charge).
The wall is now more positively charged than the balloon. As the two come in contact, the balloon sticks! This is the rule that opposites attract (positive attracts negative).
This is called an induced charge.
The wall is now more positively charged than the balloon. As the two come in contact, the balloon sticks! This is the rule that opposites attract (positive attracts negative).
This is called an induced charge.
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.
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.
