Electric Charge Explained

Definition:

All matter is made of atoms, which contain electrons, protons, and neutrons. Objects normally contain equal numbers of electrons and protons: such objects are called neutral. When an object has an imbalance in the number of electrons and protons, it is electrically charged .so we can say that,

          “       An excess or deficiency of electrons is known as charge.         ”

                                                         OR

Property of the matter by which it experience a force when placed closed to the other electrically charged matter is known as charge.

Formula:    

          Charge on the body can be determined by using the following formula,

                                                             Q=It

  Where,

Q= charge

 I=   current

 t = time.

Unit:    

In mks system unit of charge is coulomb.

 A Coulomb is defined as the number of electrons passing through a current of 1 Amp each second.

 Charge is also measured in ampere hour.

                            

Types of Charge:

1)      Positive charge.

   An object with more electrons than protons is said to carry a negative charge.

2)      Negative charge

    An object with more protons than electrons is said to carry a positive charge.

 Properties of charge:

1    Like charges always repel each other and unlike charges always attract each other.

                                        

         

                                     

 This can be seen easily in the figure that the charges which are same are repelling each other and the while the unlike charges are attracting each other.

        Charge will always be quantized. It means that the charge will be in the integral multiple of the single electronic charge.

          

3      Like energy and momentum, electric charge is also a conserved quantity. Conservation of charge means that charge can neither be created nor destroyed, but it can be transferred between objects.

Coulombs Law:     

 

 

Coulombs law states that,

“The force between the two charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them”

Mathematically, it can be expressed as,

                                              F= k q₁q₂/r²

Where,

• F  the force on each charge, + indicates repulsion, - indicates attraction
• k the electrostatic constant which is equal to  9*10⁹  Nm²/C²
• q₁ the quantity of charge 1 measured in coulombs
• q₂ the quantity of charge 2 measured in coulombs
• r the radius of separation from center of one charge to the center of the other

                                         

Coulombs law shows that the greater the charges, the greater the force.  The greater the distance between them, the smaller the force.