AC Generator

Definition:-

"The machine which is used to convert mechanical energy into electrical energy(AC current) is known as AC Generator"

Explanation:-

The device which gives us AC current(Electrical energy) by taking mechanical energy from any source(could be us) is known as Ac generator. Its construction is similar to dc generator and its working is also same almost. 

The above shown diagram is of AC generator. our need is to get the current which changes its direction after every half cycle, so to get this we need to get the current from one slip ring for one half and for other slip ring for the second half. Slip rings are connected at different ends of closed circuit. where load is connected. So that load will get Ac current.

Construction:-

It consists of following parts:-

1.Magnet

2.Slip Rings or Commutator

3.Conducting Coil or Armature

4.Carbon brushes

5. Load  

Working:-

According to the Faraday's Law of electromagnetic induction, whenever a conducting coil is move or rotates across magnetic field emf produces in it and due to this, current starts to flow through it. So in this generator when coil will move by some mechanical force across magnetic field of magnet, then there will produce an EMF and because of this, current will start to flow through it(if coil path is closed or connected to other circuit). Direction of current will be according to Fleming's right hand rule. 

As shown in this diagram, For first half rotation of coil the current will go to the load form one slip ring and for 2nd half rotation of coil the current will go from the other slip rings to the load so it is giving ac current to the load as it is changing its direction after every half cycle.

Electric Motor(AC)

Definition:-

"An electric device that converts an AC electric source into mechanical energy is known as AC electric motor"

The device that converts Electrical energy into mechanical energy for our use, we called that device electric motor.

Explanation:-

The above diagram is of ac motor that converts an ac source into mechanical energy. The problem we face in ac motor is that, ac current changes its direction after half cycle. So it is not possible for conducting coil to move in one direction for complete cycle of  ac current. To overcome this problem, we use split rings instead of commutator, so that we could reverse the direction of current. and coil could move in one direction.

Construction:-

It consists of,

1.Magnet

2.Conducting loop

3.Split rings

4.Carbon brushes

5.Ac source

Working:-

AC motor works on the same principle, as DC motor works. When we connect ac current source to the carbon brushes then through split rings current starts to flow through the wire( or conducting loop) so because there is also magnet field through wire and now current flowing through it, So according to Fleming's left hand rule, the coil will start to move. When ac current will change its direction split rings will change their direction and so coil will get same directed current and coil will move in one direction.