Daily Olympiad: Science - Fun with Magnets [20260514]

Solution

Correct: C

Magnets attract materials like iron, cobalt, and nickel. Among the given options, iron is a magnetic material, while wood, plastic, and paper are non-magnetic.

Solution

Correct: B

Like poles of magnets always repel each other. Therefore, two North poles (or two South poles) will push each other away.

Solution

Correct: C

The magnetic force of a magnet is strongest at its ends, which are called the North and South poles. The force is weakest near the center.

Solution

Correct: B

Lodestone is a naturally occurring magnet, also known as magnetite. Other options like bar, horseshoe, and cylindrical magnets are artificial magnets made by humans.

Solution

Correct: B

One of the key properties of a magnet is its directive property. When suspended freely, a magnet will always come to rest aligning itself approximately in the Earth's geographic North-South direction.

Solution

Correct: C

A compass is a device that uses a small, freely rotating magnet to indicate the North direction, thereby helping to find other directions.

Solution

Correct: C

Heating a magnet strongly is one of the ways to demagnetize it. The intense heat disrupts the alignment of its magnetic domains, causing it to lose its magnetic properties.

Solution

Correct: B

Iron, nickel, and cobalt are all magnetic materials, meaning they are attracted by a magnet. Copper is a non-magnetic material.

Solution

Correct: B

A magnet always has two poles: a North pole and a South pole. Even if you break a magnet into smaller pieces, each piece will still have a North and a South pole.

Solution

Correct: B

Unlike poles of magnets (North and South) always attract each other. Therefore, a South pole will attract a North pole.

Solution

Correct: C

You can make a temporary magnet by rubbing an iron nail (or another piece of magnetic material) repeatedly with one pole of a bar magnet in the same direction. This aligns the magnetic domains within the nail.

Solution

Correct: B

Magnets can lose their magnetism over time or due to mishandling (like heating or hammering). Proper storage, such as using keepers for horseshoe magnets or placing unlike poles together with wooden separators for bar magnets, helps to preserve their magnetic properties.

Solution

Correct: A

The space around a magnet where its magnetic force can be experienced is called the magnetic field. Iron filings can be used to visualize these field lines.

Solution

Correct: C

Regardless of how many times you cut a magnet, each resulting piece will always have both a North pole and a South pole. Magnetic poles always exist in pairs.

Solution

Correct: B

Horseshoe magnets should be stored with an iron keeper (a small piece of iron) placed across their poles. This helps to complete the magnetic circuit and prevent demagnetization.