[Physics Class Notes] on Working of Electric Bell Pdf for Exam

The electric doorbell which we all have observed in our day-to-day life is said to be a simple circuit that triggers a sound on the completion of a circuit by pressing the button. It is said to be this simplicity that makes the doorbell such a marvel. Simple devices like the doorbell in the house put the scientific principle of electromagnetism into action in a useful way. In order to understand the operations of an electric bell, we should first understand what an electromagnet is. Well, to put it in simple words an electromagnet is said to be a type of magnet in which the magnetic field is produced with the help of an electric current. Under any electrical influences electromagnet generally works as a standard magnet that is generating magnetic fields. When the power generated by an electromagnet stops, we can see the production of the magnetic field also stops. So we can say that in an electric bell an electromagnet generally forms a very important part along with the armature and the spring, armature rod, hammer, and a gong.

Once the setup is completed when the switch is pressed then the circuit loop is complete which causes the flow of current through the circuit. The arm which generally strikes the gong is connected to spring at one end and a ball of iron at the other end. This is known as a hammer or a striker. For the working of an electric bell, the magnetic field that is created by the electromagnet attracts the iron strip which is towards it when the circuit is complete. This is the moment when we hear the ringing sound since the hammer keeps hitting the gong. Meanwhile, we can say that at its rest position the hammer is held away from the gong on account of the spring attached to its arm. This is said to be an anchored arm. Working on an Electric Bell Now we can say that we have an understanding of the important parts of an electric bell. The step-by-step process of the working of the electric bell is described below: The first thing is the switch is pressed and the current flows through the circuit. Next, the electromagnet is powered and generates a magnetic field that attracts the iron strip towards it. Then the striker strikes the gong. When the striking arm strikes the gong then the contact is broken and the current stops flowing through the circuit.  This causes the electromagnet to generally lose its magnetic field. Next, the connected spring arm returns the striker to its original rest position. The contact is generally said to be restored and the slow current flow is through the circuit, provided the main switch is still pressed. The process is said to be repeated from the beginning. Electric Bell and Electromagnets. The electromagnets generally have a wide range that is put in use in all sorts of devices. Can we think of some devices which are from everyday life where we use electromagnets? The electromagnets are generally said to be used in cranes to pick up cars in scrap yards and also to separate iron from a garbage dump. They are also used in loudspeakers as well as telephones and in motors used in electric fans and washing machines, refrigerators, etc. the Electromagnets which are also used in bells or electric bells.

An Electric Bell-Introduction

An electric doorbell is a simple circuit that triggers a tone by pressing a button when the circuit is complete. It is this simplicity that makes the doorbell such a wonder. Doorbell’s simple device implements the scientific principles of electromagnetism  in a meaningful way. To understand how an electric bell works, we first need to know about electromagnet. Electromagnet is a type of magnet where magnetic field is produced using an electric current. 

When electric current flows through a wire tied around an iron rod the iron rod behave like a magnet. the magnetic effect of electric current has been used in making powerful electromagnet. the iron rod around which the wire is wound is called a solenoid. The wire is wrapped around the iron rod many times electric current is supplied to the wire, the iron Rod behaves like a magnet as long as current is supplied. the more the number of turns in the wire the stronger a magnetic effect. Electromagnet is used in electric bulbs and also in powerful cranes.

Uses of an Electromagnet:

Electromagnets are commonly used everyday appliances today. 

They are used in doorbells, hard drives, speakers and much more. Eye specialists use it for taking out foreign particles from the eyes.

They are also being used for industrial applications.

Working of an Electric Bell

The important things required for construction of an electric bell are a gong , hammer, electrometer switch and soft iron armature or hand.

Now that you understand the important things for an electric bell, let’s put up with a step-by-step explanation of how the electric bell works. 

An electric bell has Electromagnet in it. It is made up of two rods of cast iron. The iron rods have a coil wrapped around them. A metallic strip is used and is kept parallel to the coils.  This trip has a Hammer connected to it at one end. The other part of the strip is connected with the circuit. A gong is placed in such a position that it can be hit by a hammer. When electric current is passed through the circuit the cast iron rod becomes charged with electromagnetic energy and attracts the metallic strip. as a result, the metallic hammer hits the ground the circuit breaks when the metallic through peaceful towards Electromagnet and gets disconnected from the point .since there is no magnetism left an Electromagnet the spring pulls back the metallic stripped this cycle is repeated again and again in the electric bell which produces a ringing sound .that is why it is called as making brake circuit.