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Magnetism and Matter — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMagnetism and Matter3 Marks
Question
Define a magnet and write its characteristics of directive property and pole strength.
✓

Answer

Such a substance which attracts other magnetic substances such as iron etc. towards itself and when it is suspended freely, then it rests in north-south direction. Its two and equal opposite poles are separated by some distance.
Directive property : When any bar magnet is suspended freely, it always rests in a definite direction. Its one end is towards the north and the other is towards the south which are known as north pole and south pole respectively. A bar magnet always exhibits north and south direction.
Pole strength : Strength of magnetisation of magnetic poles is known as pole strength. Pole strength of both poles of a bar magnet is same. If a bar magnet is cut perpendicular to its axis, then pole strength of poles of each part will almost be same as of original magnet and if it is cut in to equal parts along its axis, then pole strength of each part will be half that of original bar magnet.

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