Induced Magnetism and Attraction

• When a bar of magnetic material is kept near or in contact with a magnet, it behaves like a magnet.
• The magnetism produced this way is called induced magnetism.

Induced Magnetism

• The temporary magnetism acquired by a magnetic material being near a magnet is called induced magnetism.
• Magnetic induction is the process where a piece of magnetic material temporarily gains magnetic properties when another magnet is nearby.
• When testing polarity at ends A and B of bar AB:
  • End A's polarity is north, opposite the magnet's near end A.
  • End B's polarity is south, similar to the magnet's near end A.
• A magnetic pole induces an opposite polarity on the near end and a similar polarity on the farther end of an iron bar.

Induction Precedes Attraction

• Ordinary iron is attracted to a magnet due to magnetic induction.
• When iron is near a magnet, the iron's nearer end gains opposite polarity through induction.
• The iron is attracted because unlike poles attract each other.
• The iron first becomes a magnet due to induction, and then attraction happens.

Induced Magnetism is Temporary

• Small iron nails form a chain when a bar magnet is brought near due to induction.
• The bar magnet induces magnetism in an iron nail, causing attraction to the magnet.
• This magnetized nail then magnetizes another nail.
• The process continues until the attraction force balances the total weight of the nail chain.
• Upon removing the magnet, the uppermost nail and the other nails lose their magnetism.
• The nails separate and fall due to gravity, revealing that magnetism acquired by induction is purely temporary.
• The magnetism only lasts as long as the inducing magnet remains nearby.

Lines of Magnetic Field

• A compass needle rests in a geographic north-south direction on a table.
• When near a magnet, the needle swings and rests in a different direction.
• The needle's direction changes depending on the compass's position around the magnet.
• One end of the needle always points toward the nearer pole of the magnet.
• This behavior results from the magnet influencing the compass.
• The region where the compass is influenced is called the magnetic field of the magnet.
• The space around a magnet where a compass needle points in a direction other than geographic north-south forms is the magnetic field.
• The effect of a magnet's magnetic field decreases as the distance from the magnet increases.
• Magnetic field is a vector quantity.
• The magnitude of magnetic field is dependent on the earth's magnetic field.

Explore induced magnetism: how magnetic materials become temporary magnets when near a magnet. Learn about polarity, magnetic induction, and why ordinary iron is attracted to magnets. Discover how attraction happens due to the induction of opposite polarities.