General Science Notes Chapter 15 Class 6 Maharashtra Board

Notes For All Chapters – General Science Class 6

Fun with Magnets

1. What is a Magnet?

A magnet is a special material that attracts iron, nickel, and cobalt. This ability to attract metals is called magnetism.

2. Discovery of Magnets

A long time ago, a shepherd named Magnes in Greece found a rock that pulled his iron stick and shoes.
This rock was later named Magnetite and is a natural magnet.
The name “Magnet” may also come from a place in Greece called Magnesia.

3. Types of Magnets

There are two types of magnets:
1. Natural Magnets – Found in nature (e.g., Magnetite).
2. Artificial Magnets – Made by people and used in different shapes, such as:

Bar Magnet (Rectangle shape)
Horseshoe Magnet (U shape)
Ring Magnet (Circular)
Disc Magnet (Flat and round)

4. Properties of a Magnet

A magnet has two poles: North Pole (N) and South Pole (S).
Like poles repel (push away), and opposite poles attract (pull together).
A freely hanging magnet always points in the North-South direction.
If a magnet is broken, each piece becomes a new magnet with both poles.
Magnets attract only magnetic materials like iron, nickel, and cobalt.

5. Magnetic and Non-Magnetic Materials

Magnetic Materials – Objects that a magnet attracts (e.g., iron nails, steel, keys).
Non-Magnetic Materials – Objects that a magnet does not attract (e.g., plastic, wood, paper).

6. Uses of Magnets

In a compass to find directions.
In cranes to lift heavy iron objects.
In electric bells and speakers.
In ATM and credit cards (Magnetic strip stores information).
In trains (Maglev Trains) for fast travel using magnetic force.

7. Electromagnets

A magnet made using electricity is called an electromagnet.
It is made by wrapping copper wire around an iron nail and connecting it to a battery.
When electricity is ON, the nail becomes a magnet.
When electricity is OFF, the magnetism disappears.
Electromagnets are used in cranes, doorbells, and electric motors.

8. Induced Magnetism

If an iron object is placed near a magnet, it also becomes a magnet for a short time.
This is called induced magnetism.
But when the main magnet is removed, the object loses its magnetism.

9. How to Take Care of Magnets

Do not heat magnets.
Do not drop or hit them hard.
Store magnets properly by keeping them with a piece of soft iron (Magnet Keeper).