(i) Electric charges generated by rubbing do not move by themselves.
a) What is the nature of these charges?
b) When charges move, what do they constitute?
Answers
Answer:
1.The electric charges generated by rubbing (or friction) are static electric charges. These electric charges remain bound on the surface of the charged object They do not move by themselves. All the insulator objects (like glass rod, plastic comb, plastic scale, plastic straw, ball pen refill and rubber ballon, etc.)
2.Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field. There are two types of electric charge: positive and negative (commonly carried by protons and electrons respectively). Like charges repel each other and unlike charges attract each other.
3.When charges move, they constitute an electric current. Electroscope; It is a device that can be used to test whether an object is carrying charge or not. Electroscope consists of closely placed two metallic (aluminium) foils or strips.
Answer:
(1) The electric charges generated by rubbing (or friction) are static electric charges. These electric charges remain bound on the surface of the charged object They do not move by themselves. All the insulator objects (like glass rod, plastic comb, plastic scale, plastic straw, ball pen refill and rubber ballon, etc.)
(2) (a) If both q
1
and q
2
are positive, the electrostatic force between these will be repulsive.
However, if one of these charges is positive and is greater than the other negative charge, the electrostatic force between them will be attractive.
Thus, the nature of force between them can be repulsive or attractive.
(b) If both q
1
and q
2
are −ve, the force between these will be repulsive.
However, if one of them is −ve and it is greater in magnitude than the second +ve charge, the force between them will be attractive.
Thus, the nature of force between them can be repulsive or attractive.
(3) When charges move, they constitute an electric current. ... The process of transfer of charge from a charged object to the earth is called earthing. 7. The process of electric discharge between clouds and the earth or between different clouds causes lightning.