When soap is rubbed on a stain curry on a white cloth, why does it becomes reddish brown and turns yellow again when the cloth is washed with plenty of water?

Why clothes become water-proof when wax is rubbed on them?

Why does rain water normally have a pH of about 5.6 ? When does it become acid rain ?

Frictional electricity The electricity developed in bodies when they are rubbed with each other is called frictional electricity. There are two kinds of charges, namely positive and negative. Like charges repel each other and unlike charges attract each other. when a glass rod is rubbed with silk cloth, glass rod becomes positively charged are silk acquires the same amount of negative charge. the concept of positive and negatice charges was introduced by Benjamin Franklin. The charge is always quantised and conserved in a system. The number of electrons for one coulomb of charge is

Frictional electricity The electricity developed in bodies when they are rubbed with each other is called frictional electricity. There are two kinds of charges, namely positive and negative. Like charges repel each other and unlike charges attract each other. when a glass rod is rubbed with silk cloth, glass rod becomes positively charged are silk acquires the same amount of negative charge. the concept of positive and negatice charges was introduced by Benjamin Franklin. The charge is always quantised and conserved in a system. A body can be negatively charged by

Frictional electricity The electricity developed in bodies when they are rubbed with each other is called frictional electricity. There are two kinds of charges, namely positive and negative. Like charges repel each other and unlike charges attract each other. when a glass rod is rubbed with silk cloth, glass rod becomes positively charged are silk acquires the same amount of negative charge. the concept of positive and negatice charges was introduced by Benjamin Franklin. The charge is always quantised and conserved in a system. Sure test of electrification is

Frictional electricity The electricity developed in bodies when they are rubbed with each other is called frictional electricity. There are two kinds of charges, namely positive and negative. Like charges repel each other and unlike charges attract each other. when a glass rod is rubbed with silk cloth, glass rod becomes positively charged are silk acquires the same amount of negative charge. the concept of positive and negatice charges was introduced by Benjamin Franklin. The charge is always quantised and conserved in a system. When a glass rod is rubbed with silk, it acquires a positive charge becuause:

Frictional electricity The electricity developed in bodies when they are rubbed with each other is called frictional electricity. There are two kinds of charges, namely positive and negative. Like charges repel each other and unlike charges attract each other. when a glass rod is rubbed with silk cloth, glass rod becomes positively charged are silk acquires the same amount of negative charge. the concept of positive and negatice charges was introduced by Benjamin Franklin. The charge is always quantised and conserved in a system. The law of force that governs the force between two electric charges was discovered by

Why it is easer to wash clothes in hot water soap solution?