Exploring Magnets – CBSE NCERT Study Resources

We studied that magnets attract ferromagnetic materials like iron, nickel, and cobalt. Our textbook shows steel contains iron, making it magnetic, while plastic is non-magnetic.

Our textbook shows magnets have north (N) and south (S) poles. Like poles (N-N or S-S) repel due to magnetic field alignment.

We learned Earth has a magnetic field with north and south poles. The compass needle (a tiny magnet) aligns with it.

Our textbook states magnetism is strongest at poles. The middle (neutral zone) has negligible force.

We studied that Earth acts like a giant magnet with north and south poles. The compass needle aligns with Earth’s magnetic field, pointing north.

• NCERT example: A compass helps sailors navigate.
• Real-life use: Hikers use compasses to find directions in forests.

Magnets attract ferromagnetic materials like iron, nickel, or cobalt due to their atomic structure.

• NCERT example: Iron filings stick to magnets.
• Real-life use: Fridge doors use magnets to hold notes.

We learned that like poles repel and unlike poles attract.

• NCERT activity: Place two bar magnets with north poles facing each other; they push apart.
• Real-life use: Maglev trains use repulsion to float.

Dropping or heating a magnet misaligns its magnetic domains, reducing strength.

• NCERT method: Stroke the magnet with another strong magnet in one direction.
• Real-life use: Speakers use magnets to produce sound.

Riya noticed only iron nails stick to the fridge, not plastic buttons.

Our textbook shows magnets attract ferromagnetic materials like iron due to their magnetic domains.

• Iron nails are magnetic materials (attracted).
• Plastic is non-magnetic (no attraction).

Aarav thinks broken magnet pieces retain poles.

We studied that every magnet has two poles, even if split.

• Each piece becomes a smaller magnet (NCERT activity).
• Example: Breaking a compass needle still shows poles.

This matches our experiment with iron filings around broken pieces.

Priya used magnets to separate iron powder from sand.

Magnets attract magnetic substances like iron (NCERT Fig. 13.4).

1. Mix iron powder and sand.
2. Move a magnet over it; iron sticks.

Real-world use: Recycling plants separate metals from waste.

Compass needle moved near a steel ruler.

Our textbook states compasses align with Earth’s magnetic field unless disturbed.

• Steel is magnetic and disrupts the needle.
• Precaution: Keep compass away from metal objects (NCERT example: avoiding keys).

Magnets have two poles: the north pole and the south pole. According to the law of magnets, like poles repel and unlike poles attract each other. This is why:

• When the north pole of one magnet is brought near the south pole of another, they attract because they are unlike poles.
• When two north poles are brought close, they repel because they are like poles.

This behavior is fundamental to how magnets interact and is used in many devices like compasses and electric motors.

No, a magnet cannot exist with just one pole. Every magnet, no matter how small, always has both a north pole and a south pole. This is known as the law of magnetic poles.

When a magnet is broken into smaller pieces:

• Each piece becomes a new magnet with its own north and south poles.
• The poles rearrange themselves so that no single piece has only one pole.

This property is why magnets are used in various applications, as even tiny fragments retain their magnetic properties.

(a) The property demonstrated here is the magnetic poles behavior: like poles repel and unlike poles attract. This is a fundamental characteristic of magnets.

(b) This property is used in many daily applications. For example, refrigerator doors use magnets to stay closed. The door has a magnetic strip that attracts the metal frame, ensuring a tight seal to keep food fresh.

(a) The pattern formed by the iron filings represents the magnetic field lines of the magnet. These lines show the direction and strength of the magnetic force around the magnet.

(b) The iron filings arrange themselves along the magnetic field lines because they are temporary magnets. When placed near a magnet, they align in the direction of the magnetic force, making the invisible field visible.

The refrigerator door closes automatically because it has a magnetic strip attached to it, which interacts with the metal frame of the refrigerator. This is due to the magnetic force between the strip and the frame.

Iron pins stick to the door because the door is made of or contains magnetic material, which attracts ferromagnetic substances like iron.

One other household item that uses this property is a magnetic cabinet latch, which keeps doors securely closed using magnets.

The ends of the magnet where the iron filings clustered more densely are called the poles of the magnet (specifically, the north and south poles).

The iron filings cluster more at the poles because the magnetic force is strongest at these points. The poles have the highest concentration of magnetic lines of force, which attract the iron filings.

If you break a bar magnet into two pieces, each new piece will still have its own north and south poles. This happens because magnetic properties are retained even when the magnet is divided.

(a) The property demonstrated here is the law of magnets, which states that like poles repel and unlike poles attract each other. This is a fundamental behavior of magnets.

(b) To separate iron nails from a mixture of sand and iron nails, we can use a magnet. Here’s how:

• Bring a strong magnet close to the mixture.
• The magnetic force will attract the iron nails, sticking them to the magnet.
• Sand, being non-magnetic, will remain behind.
• Once the nails are attached, they can be easily separated by pulling the magnet away.

This method is efficient and commonly used in recycling and waste separation.

(a) The magnet aligns in the north-south direction because the Earth itself behaves like a giant magnet with its own magnetic poles. The north pole of the magnet is attracted to the Earth’s magnetic south pole (near the geographic north), causing the alignment.

(b) This property is extremely useful in navigation:

• A compass, which contains a small magnetized needle, uses this principle to point towards the Earth’s magnetic north.
• Travelers, sailors, and explorers use compasses to find directions when maps or landmarks are unavailable.
• It helps in determining routes accurately, especially in forests, oceans, or unfamiliar terrains.

This natural alignment makes magnets indispensable in direction-finding tools.

The bar labeled A is likely a magnet because it attracts iron nails and deflects the compass needle, both of which are properties of a magnet. Bar B does not show these effects, so it is not a magnet.

The deflection of the compass needle demonstrates the magnetic property of magnets. A compass needle is itself a small magnet, and like poles repel while unlike poles attract. When bar A is brought near the compass, its magnetic field interacts with the needle's field, causing deflection.

This experiment also shows that magnets exert a non-contact force, as the needle moves without direct touch.

The experiment demonstrates the Law of Magnetic Poles, which states that like poles repel (north-north or south-south) and unlike poles attract (north-south).

This property is used in many everyday applications. For example, in refrigerator doors, small magnets are embedded in the door seal. The opposite poles of these magnets attract the metal frame, ensuring the door closes tightly and keeps the cold air inside.

Another example is in electric motors, where the repulsion and attraction between magnets help convert electrical energy into mechanical motion.

Magnets have two poles: the north pole and the south pole. According to the law of magnets, like poles repel and unlike poles attract each other. This is because the magnetic force between them behaves in a specific way:

• When two unlike poles (north and south) come close, the magnetic field lines connect, creating an attractive force.
• When two like poles (north-north or south-south) come close, the field lines push away, causing repulsion.

This property is used in many devices like compasses and electric motors to control movement using magnetic forces.

The pattern formed by the iron filings represents the magnetic field lines of the magnet. Here's why:

• The iron filings align themselves along the invisible magnetic field created by the magnet.
• The field lines emerge from the north pole and enter the south pole, forming curved paths.
• The closer the lines, the stronger the magnetic force in that region.

This experiment helps visualize how magnets interact with materials and their surroundings. It also explains why magnets attract ferromagnetic materials like iron, as these materials get influenced by the magnetic field.