How does a doorbell use electricity, electromagnets, and magnets to produce mechanical energy?

In a doorbell  electricity is responsible for the functioning of the electromagnet. The electromagnet due to its magnetic property pull the armature which then moves the hammer towards the gong and the door bell rings.

In this way a doorbell use electricity, electromagnets and magnets

to produce mechanical energy.

Explanation:

The main parts of a electric door bell are:

a horseshoe electromagnetA soft iron armatureA hammer,A gongA metallic stripAn adjusting screwA switchA battery or source of electricity.

Structure:( Refer to the attachment for diagram)

Description:

The armature of the bell is fixed to the metallic strip.The hammer is attatched to the end of armature.The springy metallic strip remains in contact with adjusting screw when switch is not pressed.The horse shoe electromagnet is a U-shaped soft iron piece having a coil wound on it such that the winding on its two arm is in opposite direction..The two ends of the coil are connected to the terminals as shown in the figure.Between terminal T₁ and T₂ the battery (electric source)  with a switch is joined.

Working:

As soon as the switch is pressed, the electric current passes throught the horse shoe electromagnet and the magnet resumes its magnetic property.Being a magnet it attracts the armature.Armature moves and the hammer strikes the gong and bell rings. Here electrical energy ultimately changes into mechanical energy.once the switch is off the current flow stops and the electromagnet gets demagnetized.And the armature comes back to its mean position due to the spring action of metallic strip.The metallic strip then comes back in contact with the adjusting screw.