What is magnetic force?

• A force that acts between electric charges

• A force that acts between magnets or moving electric charges

• A force that acts only on stationary objects

• A force that acts only in liquids

Answer explanation

Magnetic force is the interaction between magnets or moving electric charges. It does not act only on stationary objects or in liquids, making the correct choice the one that includes both magnets and moving charges.

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The interactions of magnets can be described as:

• They attract or repel each other depending on their poles.

• They always attract each other.

• They have no effect on each other.

• They only repel each other.

Answer explanation

Magnets interact by attracting or repelling each other based on their poles: like poles repel, while opposite poles attract. This makes the first choice the correct answer.

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The magnetic field lines of a magnet:

• Start from the north pole and end at the south pole outside the magnet.

• Start from the south pole and end at the north pole outside the magnet.

• Are straight lines between the poles.

• Do not form closed loops.

Answer explanation

The correct choice states that magnetic field lines start from the north pole and end at the south pole outside the magnet. This reflects the conventional direction of magnetic field lines, which always form closed loops.

Magnetic declination is:

• the angle between magnetic north and true north

• the strength of the Earth's magnetic field

• the process of magnetizing a material

• the distance between two magnetic poles

Answer explanation

Magnetic declination refers to the angle between magnetic north (the direction a compass points) and true north (geographic north). This is crucial for navigation, making the first answer choice correct.

A magnetic domain is:

• A region within a material where the magnetic moments are aligned in the same direction.

• A type of electric field.

• A particle with a magnetic charge.

• A device used to measure magnetism.

Answer explanation

A magnetic domain is defined as a region within a material where the magnetic moments are aligned in the same direction, which is crucial for understanding magnetism in materials.

Magnetosphere is:

• the region around a planet dominated by its magnetic field

• the layer of gases surrounding a planet

• the solid outer shell of a planet

• the process of generating magnetic fields

Answer explanation

The magnetosphere is defined as the region around a planet where its magnetic field dominates. This choice correctly describes the area influenced by the planet's magnetic forces, unlike the other options.

A ferromagnetic material is:

• A material that is strongly attracted by a magnet

• A material that does not conduct electricity

• A material that is transparent to light

• A material that is a good insulator

Answer explanation

A ferromagnetic material is characterized by its strong attraction to magnets, making the first choice correct. The other options do not accurately describe ferromagnetic materials.

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What will happen if you were to break a magnet in half?

• Each piece will become a new magnet with its own north and south poles.

• The magnet will lose its magnetism completely.

• Only one piece will remain magnetic.

• The pieces will attract each other and form a single magnet again.

Answer explanation

When a magnet is broken in half, each piece retains its magnetic properties and becomes a new magnet, each with its own north and south poles. This is a fundamental property of magnets.

A magnet can be demagnetized by:

• Heating it

• Cooling it

• Polishing it

• Painting it

Answer explanation

A magnet can be demagnetized by heating it, as high temperatures disrupt the alignment of magnetic domains. Cooling, polishing, or painting do not effectively demagnetize a magnet.

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What creates a magnetic field?

• Electric current

• Sound waves

• Light rays

• Heat energy

Answer explanation

A magnetic field is created by electric current. When electric charges move, they generate a magnetic field around them, which is the fundamental principle behind electromagnetism.

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