Demagnetisation of magnets

Qn. What is demagnetisation?

Demagnetisation is a way of making a magnet lose its magnetism.
Qn. Write down the different ways of demagnetising a magnet.
By hammering a magnet.
By heating a magnet.
By leaving a magnet to rust.
By keeping a magnet with like poles near each other for a long time.
By keeping a magnet while facing in the East to West direction.
By passing alternating currents through a magnet.
By boiling a magnet in water.
Qn. State the ways of keeping a magnet safe.
Keeping magnets in iron keepers.
Painting magnets
Storing magnets with their poles facing in the North – South direction.
Qn. Give the uses of magnets
Magnets are used in radios.
Magnets are used in microphones.
Magnets are used in loudspeakers.
Magnets are used in generators to produce electricity.
Magnets are used in dynamos to produce electricity.
Magnets are used by doctors to remove magnetic substances from delicate body organs.
Magnets are used by watch repairers to hold tiny nails.
Magnets are used in doors of refrigerators
Magnets are used in cranes to list scrap.
Magnets are used to hold cutlery on walls.
Magnets are used in electric bells.

Qn. How does an electric bell work?

When the switch is pressed, current starts flowing and the soft iron core gains magnetism.
When the soft iron core gains magnetism, it attracts the soft iron armature.
The hammer attached to the soft iron armature hits the gong and sound is produced.
The metal strip is pulled away from the contact screw and the electro magnet becomes demagnetised.
Name the appliances that use both magnets and electricity.
Radios
Electric bells
Loud speakers
Electric motors
Refrigerators
Television sets.
Qn. Give examples of appliances that use magnets only
Magnetic compasses.
Magnetic tapes