Some objects can be charged by rubbing with other objects.
When we rub two objects, made of different substances, together the charge they acquire are opposite to each other.
STATIC FRICTION
The chemical charge generated by rubbing is called static electricity because these charges do not transmit. There are two types of charges-positive charge and negative charge.
NEGATIVE CHARGE
When the charge of an object is due to the excess of electrons, it is called a negative charge.
POSITIVE CHARGE
When the charge of an object is due to the loss of electrons, it is called a positive charge.
ELECTROSCOPE
Electroscope is a device used to test whether an object is carrying charge or not.
EARTHING
The process of transfer of charges from a charged object to the Earth is called earthing.
Earthing is provided in electrical wiring in building to protect us from electrical shocks, in case of any leakage of electrical current.
LIGHTNING
The process of electric discharge between clouds and the earth or between different clouds causes lightning. It is also called electric discharge. Lightning strike could destroy life and property.
Lightning conductors cam protect buildings from the effects of lightning.
Thunder is the loud noise which accompanies lightning.
Thunderstorm is a storm accompanied by thunder and lightning.
LIGHTNING ROD
A lightning rod is a device used to secure tall buildings from the effect of a lightning conductor.
A metallic rod taller than the height of the building is installed in the walls of the building during its construction to protect it from the effect of lightning.
EARTHQUAKE
An earthquake is a sudden shaking or trembling of the Earth.
Earthquake is caused by a disturbance deep inside the Earth’s crust.
It is not possible to predict the occurrence of an earthquake.
Earthquakes tend to occur at the boundaries of Earth’s plates. These boundaries are known as fault zones.
The destructive energy of an earthquake is measured on the Richter scale. The earthquake measuring 7 or more on the Richter scale can cause severe damage to life and property.
SEISMOGRAPH
The seismic waves are recorded by an instrument in the form of a graph called the seismograph.
TSUNAMI
Earthquakes may cause tsunamis in oceans, resulting in huge damage in coastal areas.
TRANSFER OF CHARGE
Electrical charge can be transferred from a charged object to another through a metal conductor.