Some Natural Phenomena NCERT Science Class VIII Chapter 15 Summary Note

When we take off clothes in dark, we see a spark and crackling sound. Because
- Our body gets rubbed with clothes. 
- This produces charges. 
- When charges meet, they cause spark and crackling sound. 

Charged object
Object having electric charge. 
Example- Rubbed balloon

Electric charges are generated by rubbing. 

Types of charges- 
(a) Positive charge 
(b) Negative charge 

Interaction between charges
-Like charges repel each other. 
-Unlike charges attract each other. 

It is a convention to call the charge acquired by a glass rod when it is rubbed with silk as positive. 
The another kind of charge is said to be negative. 

Static charge 
Charge that do not move. 

Electric current
Movement of charges , is electric current. 


Electroscope 
A device that test whether an object is charged or not, is called electroscope. 


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