Magnetism Practice Questions
19 free Magnetism practice questions for the General Science. Tap an option to answer — you get instant feedback, the correct answer, and a detailed explanation for every question.
Which material is strongly attracted by a magnet?
- A Copper
- B Zinc
- C Iron
- D Aluminum
Correct answer: Iron
Iron is ferromagnetic, so its magnetic domains align readily in an external field and it is strongly attracted to a magnet. Copper, zinc, and aluminum are metals but are not ferromagnetic, so a magnet does not attract them.
The region around a magnet where magnetic forces can be detected is called the:
- A Magnetic pole
- B Magnetic field
- C Magnetic domain
- D Magnetic flux
Correct answer: Magnetic field
A magnetic field is the area surrounding a magnet where magnetic forces act on other magnetic materials or moving charges. It is commonly represented by magnetic field lines.
Which instrument is used to detect the presence of a magnetic field?
- A Ammeter
- B Voltmeter
- C Galvanometer
- D Compass
Correct answer: Compass
A compass contains a small magnetized needle that aligns with the Earth's magnetic field. When placed near another magnet or current-carrying conductor, the needle deflects, indicating a magnetic field.
What happens when like poles of two magnets are brought close together?
- A They repel each other
- B They attract each other
- C They lose their magnetism
- D Nothing happens
Correct answer: They repel each other
Like magnetic poles repel each other due to the interaction of their magnetic fields. This is a fundamental property of magnetism where similar poles push apart.
The SI unit of magnetic flux density is:
- A Tesla
- B Volt
- C Ampere
- D Weber
Correct answer: Tesla
The tesla (T) is the SI unit of magnetic flux density, which measures how concentrated a magnetic field is. One tesla equals one weber of magnetic flux per square metre.
Which pole of a freely suspended magnet points toward the geographic north?
- A South pole
- B Both poles equally
- C Neither pole
- D North pole
Correct answer: North pole
The north pole of a magnet points toward the Earth's geographic north when freely suspended. This occurs because the Earth itself acts like a giant magnet.
Magnetic field lines around a bar magnet emerge from:
- A South pole and enter north pole
- B Both poles equally
- C Center of magnet
- D North pole and enter south pole
Correct answer: North pole and enter south pole
Magnetic field lines originate from the north pole of a magnet and enter the south pole outside the magnet. Inside the magnet, they travel from south to north, forming closed loops.
Which scientist discovered that electric current produces a magnetic field?
- A Hans Christian Ørsted
- B Michael Faraday
- C Charles-Augustin de Coulomb
- D André-Marie Ampère
Correct answer: Hans Christian Ørsted
Hans Christian Ørsted discovered in 1820 that a current-carrying wire can deflect a compass needle. This demonstrated that electric currents create magnetic fields.
Which rule helps determine the direction of the magnetic field around a current-carrying conductor?
- A Right-hand thumb rule
- B Fleming's left-hand rule
- C Lenz's law
- D Coulomb's law
Correct answer: Right-hand thumb rule
The right-hand thumb rule states that if the thumb points in the direction of current, the curled fingers indicate the direction of the magnetic field around the conductor.
What type of magnet is created when electric current flows through a coil of wire?
- A Permanent magnet
- B Natural magnet
- C Bar magnet
- D Electromagnet
Correct answer: Electromagnet
An electromagnet is produced when electric current passes through a coil of wire, usually wrapped around a soft iron core. The magnetic field exists only while current flows.
Which material is commonly used as the core in an electromagnet?
- A Copper
- B Aluminum
- C Stainless steel
- D Soft iron
Correct answer: Soft iron
Soft iron is commonly used as the core of an electromagnet because it magnetizes easily and loses magnetism quickly when the current stops. This makes it ideal for controlled magnetic applications.
Which phenomenon explains the production of electricity using magnets and coils?
- A Electromagnetic induction
- B Magnetic hysteresis
- C Electrostatic induction
- D Nuclear magnetic resonance
Correct answer: Electromagnetic induction
Electromagnetic induction occurs when a changing magnetic field induces an electric current in a conductor. This principle is used in generators and transformers.
Which law describes the direction of induced current in electromagnetic induction?
- A Lenz's law
- B Ampère's law
- C Coulomb's law
- D Ohm's law
Correct answer: Lenz's law
Lenz's law states that the direction of induced current is such that it opposes the change in magnetic flux that produced it. This ensures conservation of energy in electromagnetic systems.
Which property describes materials that are weakly repelled by magnetic fields?
- A Diamagnetism
- B Ferromagnetism
- C Paramagnetism
- D Hysteresis
Correct answer: Diamagnetism
Diamagnetic materials are weakly repelled by magnetic fields because their electrons create small opposing magnetic moments. Examples include bismuth and copper.
What is the basic unit of magnetism in ferromagnetic materials called?
- A Magnetic atom
- B Magnetic domain
- C Magnetic particle
- D Magnetic molecule
Correct answer: Magnetic domain
A magnetic domain is a small region within a ferromagnetic material where atomic magnetic moments align in the same direction. When many domains align, the material becomes magnetized.
Which phenomenon occurs when a changing magnetic field produces an electric field?
- A Magnetostatic shielding
- B Electromagnetic induction
- C Nuclear magnetic resonance
- D Magnetic hysteresis
Correct answer: Electromagnetic induction
Electromagnetic induction occurs when a time-varying magnetic field induces an electric field and current in a conductor. This principle forms the basis of electric generators.
Which scientist formulated the laws describing electromagnetic induction?
- A Michael Faraday
- B Albert Einstein
- C Alessandro Volta
- D Heinrich Hertz
Correct answer: Michael Faraday
Michael Faraday discovered electromagnetic induction in 1831. His work showed that a changing magnetic field can produce an electric current in a nearby conductor.
Which device uses electromagnets to convert electrical energy into mechanical motion?
- A Electric generator
- B Electric motor
- C Transformer
- D Capacitor
Correct answer: Electric motor
An electric motor works by using electromagnets to produce forces that cause rotation. Electrical energy is converted into mechanical motion through magnetic interactions.
Which property determines how strongly a material can be magnetized?
- A Magnetic permeability
- B Electrical resistance
- C Thermal conductivity
- D Magnetic declination
Correct answer: Magnetic permeability
Magnetic permeability measures how easily a material can support the formation of a magnetic field within it. Materials with high permeability, such as iron, magnetize more easily.