Question

1. Take a square cardboard and mark the directions on it. Place a pot
nlled with water at the centre of the cardboard. Take a magnetized
needle. Stick it to a small piece of a cardboard by means of a sticking
tape. Place the piece of cardboard with the needle, on the surface of
waterin the pot. What do you observe?
Magnetic needle

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Answer 1

Place a steel bar on a table. Take two bar magnets. Place two

opposite poles of the two bar magnets at the centre of the steel bar, Drag these

poles apart, one to the 'A' end of the steel bar, and the other to the 'B' end

Repeat this 15 to 20 times. Now take the steel bar near iron fillings and observe.

Hang the steel bar freely and observe.

This method of magnetisation is called the double-touch method. The magnetism

generated by this method lasts longer compared to that generated by the single

touch method.