What is the difference between AC and DC current?

Full Form of AC is Alternative current and of DC is Direct current. Direct current is flowing in one direction. Direct current example is battery which flows only in one direction. And Alternative current change it's direction in some microsecond time interval. Alternative current example is the current in your house.

How electric generator works?

In the previous article I had defined the mechanism of Electric motor. And in this article I am defining the mechanism of Electric Generator. Electric Generator works on same principal on which Electric motor works.
In Electric motor electric current is passing through wire in magnetic field which force the wire and rotates. And in Electric generator wires is rotated in Magnetic field which generates electric current.Below is the picture of electric generator.

You can see the Magnets and armature are in same ways as in motor. Here a handle is added with armature to rotate the armature.Armature ends are connected with conductor rings. Armature one end is connected to only one ring and another end is connected to only other ring. Both rings are touching brushes. When Armature rotates ring also rotates but brushes are stating just touching the ring. When Armature is rotated by handle then armature is entering and exiting in magnetic field. Principle is that, when you move a coil back and forth in magnetic field there is electricity generated in coil.So in this mechanism armature is entering and exiting in magnetic field so current is generated. And in the article of motor I have already described the Fleming's Left-Hand Rule. So in this architecture current direction is decided by direction of force and magnetic field. So current direction will change interchangeably.

You can see a bulb in picture. When armature rotates current will be generated and bulb will light.

How electric motor works?

Electric motor is a very important machine component. This is used in many machine i.e. Fan, Washing machine, Electric car. Did you ever thought that how it works. In this article I am explaining electric motor mechanism.

Main components of electric motor are Permanent magnets, Armature(Hard wire) commutators and Brushes. Following is the image of electric motor.

In the above picture you can see two magnets facing their opposite poles towards each other, a armature (Loop of hard coil), commutators and brushes. Electric current is passing through armature and generating a force that rotating the armature. You can see the force indicated by orange arrow. You can figure out force direction with the help of Fleming's Left-Hand Rule as in below picture. 

According to this rule if you hold out your thumb, first finger and second finger of Left hand so that all three are right angles and point your first finger in the direction of field and second finger in the direction of current then thumb will indicates the direction of force. 

So by force armature starts rotating. You can see in the picture that there are two commutators connected with armature ends and touching brushes. When armature rotates so commutator rotates. When armature completed half rotation then automatically commutators exchange the brush because brushes are fixed. So current flow change repeatedly. This helps to complete the full rotation otherwise armature go static after half rotation. In this way armature keep rotating till current is flowing.

What is electricity?

Electricity is a form of energy. It can flow from one place to another place via a medium (metal). When electricity stored at a place then it's called static electricity and when flow from one place to another place it's called current electricity.

Actually it's a hoard of electrons. Each electron contains some amount of charge. So as big hoard of electrons as much electricity will be there.

Electrons can freely move from place of excess electrons to place of less electrons via a medium (metal) to balance the numbers of electrons.

By allowing electrons to move from one place to another place another type of energy can be created such as kinetic energy, heat energy etc.