Wheatstone Bridge—
It is arrangement of four resistances used to determine one unknown resistance with the help of remaining three resistances.
In this arrangement we arrange four resistances P, Q, R and S as shown in figure.
On applying Kirchhoff’s Law
Properties of charges
1.Conserved
Charge is conserved in nature means it neither be created Nor be destroyed. It is transferred from one body to other body.
2. Additive
The total electric charge on an object is equal to the algebraic sum of all the electric charges distributed on the different parts of that object.
q=q1+q2+q3+.......
Frictional electricity-
When two different objects (such as a glass rod and Silk) are rubbed together they get electrified. It happens due to transfer of electrons from one object to another object due to the difference in their electro negativities. The object that gains electrons becomes negatively charged while the object that loses electrons becomes positively charged.
Electrostatic induction
Electric charge and two kinds of charges--
All the substances are made up of small particles called atoms, which are made of three elementary particles, namely electrons, protons and neutrons. Studies say that it neutron is also made up of one proton and one electron.
So we can say that electrons and protons are are the basic particles which constitute the atoms and all the world is a combination of atoms. So there are only two particles - electrons and protons.