Test: Magnetism - UPSC MCQ

• Iron, Nickel, and Cobalt are ferromagnetic materials, meaning they can be magnetized and are attracted to magnets.
• Copper, on the other hand, is a non-ferromagnetic metal.
• It does not have the magnetic properties like Iron, Nickel, or Cobalt, making it unaffected by magnetic fields.
• In everyday terms, while Copper can conduct electricity, it won't stick to a magnet.

The poles of a magnet are referred to as the North pole (N) and the South pole (S).

Magnetic field lines around a bar magnet start from the North Pole and end at the South Pole, forming a closed loop.

The strength of a magnet is determined by its magnetic moment, which is a property related to the alignment and arrangement of its magnetic domains.

A magnet will always attract ferromagnetic materials, which are strongly attracted to magnetic fields. Diamagnetic and paramagnetic materials may also be weakly attracted, but to a lesser extent.

Iron is a natural magnet and can exhibit magnetic properties without the need for external influence.

The phenomenon of a temporary magnet losing its magnetism when the inducing magnetic field is removed is called demagnetization.

The SI unit of magnetic field is the Tesla (T).

Horseshoe magnets are commonly used in electric bells and speakers due to their strong magnetic field and convenient shape.

In magnetism, opposite or unlike poles (north and south) attract each other, while similar or like poles (north-north or south-south) repel each other.

The magnetic field inside a solenoid, which is a tightly wound coil of wire, is uniform.

Steel is a ferromagnetic material that can be easily magnetized. Aluminum and copper are non-magnetic materials, and wood is diamagnetic.

The strength of a magnetic field is strongest near the poles of a magnet.

The diameter of the wire does not significantly affect the strength of the magnetic field produced by an electric current. Factors such as the length of the wire, the material of the wire, and the current flowing through the wire have a more significant impact.

Retentivity is the property of a material to retain some magnetism even after the removal of an external magnetic field.

Magnetic field lines do not intersect with each other. They form continuous, closed loops.

Ampere's Law states that the magnetic field produced by a current-carrying wire is directly proportional to the current and inversely proportional to the distance from the wire.

A magnetometer is the device used to measure the strength and direction of a magnetic field.

An MRI (Magnetic Resonance Imaging) machine utilizes electromagnets to generate strong magnetic fields for medical imaging purposes.

The process of aligning the domains of a magnetic material to produce a magnet is called magnetization.