Electric and Magnetic Fields Questions and Answers for Viva

Answer-1: An electric field is a region around a charged object where a force is exerted on other charged objects. It is a vector quantity represented by electric field lines.

Answer-2: The SI unit of electric field strength is volts per meter (V/m).

Answer-3: Gauss's law states that the electric flux through any closed surface is equal to the total charge enclosed by that surface divided by the electric constant (ε_o).

Answer-4: Capacitance is a measure of an object's ability to store electric charge per unit voltage. It is defined as the ratio of the magnitude of the charge on one of the conductors to the voltage difference between them.

Answer-5: Insulators have high resistance to the flow of electric charge and do not allow electric fields to penetrate easily, whereas conductors have low resistance and allow electric fields to penetrate freely.

Answer-6: A magnetic field is a region around a magnet or a moving electric charge where magnetic forces are experienced. It is a vector quantity represented by magnetic field lines.

Answer-7: The SI unit of magnetic field strength is the tesla (T).

Answer-8: Ampère's law states that the magnetic field around a closed loop is directly proportional to the electric current passing through the loop.

Answer-9: A permanent magnet produces a magnetic field due to the alignment of its atomic dipoles, whereas an electromagnet produces a magnetic field when an electric current flows through a coil of wire.

Answer-10: Magnetic flux is a measure of the total magnetic field passing through a given area. It is the product of the magnetic field strength and the area perpendicular to the field.

Answer-11: Faraday's law states that a changing magnetic field induces an electromotive force (emf) or voltage in a conductor.

Answer-12: Lenz's law states that the direction of the induced current in a conductor is such that it opposes the change that produced it.

Answer-13: Magnetic materials are materials that are attracted to magnets and can be magnetized, whereas non-magnetic materials are not attracted to magnets and cannot be magnetized easily.

Answer-14: Magnetic domains are regions within a material where the magnetic moments of atoms are aligned in the same direction, resulting in a net magnetic field.

Answer-15: Magnetic hysteresis refers to the phenomenon where the magnetization of a material lags behind the applied magnetic field, creating a loop-shaped hysteresis curve when the field is cycled.

Answer-16: In electromagnetic waves, electric and magnetic fields are perpendicular to each other and oscillate in phase. Changes in one field induce changes in the other, propagating energy through space.

Answer-17: Electric fields exert forces on charged particles, causing them to accelerate or decelerate, while magnetic fields exert forces perpendicular to the direction of motion of charged particles, causing them to move in curved paths.

Answer-18: Applications include electric power generation and distribution, motors and generators, transformers, magnetic resonance imaging (MRI) in medicine, electric motors in appliances, and electromagnetic induction in wireless charging and communication technologies.