10th Physics Chapter 6: Electromagnetism

Sr #	Questions	A	B	C	D
1	When a current-carrying wire is placed perpendicular to a magnetic field, the force experienced by the wire is:	Maximum	Minimum	Zero	Indeterminate
2	Mutual induction is the principle behind the operation of which device?	Generator	Motor	Transformer	Resistor
3	A step-down transformer is commonly used in:	Power distribution networks	Electrical substations	High-voltage transmission lines	Electronic devices
4	The magnitude of the force experienced by a current-carrying conductor in a magnetic field depends on:	The length of the conductor	The material of the conductor	The strength of the magnetic field	All of the above
5	What is the basic principle behind the operation of a transformer?	Faraday's law of electromagnetic induction	Ohm's law	Newton's second law of motion	Hooke's law of elasticity
6	Which of the following factors does not affect the magnitude of the induced emf in a coil of an AC generator?	Speed of rotation	Number of turns in the coil	Strength of the magnetic field	Length of the conductor
7	What is the function of the commutator in a DC motor?	It reverses the direction of current in the armature coil	It regulates the speed of the motor	It increases the torque produced by the motor	It provides a path for current to flow to the armature
8	What is the direction of the magnetic field around a current-carrying wire, as per the right-hand thumb rule?	Along the direction of the current	Opposite to the direction of the current	Perpendicular to the direction of the current	Tangential to the direction of the current
9	Which part of a transformer is responsible for transferring energy from the primary coil to the secondary coil?	Iron core	Insulating material	Copper wire	Voltage source
10	What is the shape of the magnetic field around a straight steady current-carrying wire?	Circular	Spherical	Elliptical	Straight
11	Which type of transformer increases the voltage from the primary coil to the secondary coil?	Step-up transformer	Step-down transformer	Isolation transformer	Autotransformer
12	What is the principle behind the turning effect on a current-carrying coil in a magnetic field?	Ampere's law	Faraday's law of electromagnetic induction	Fleming's left-hand rule	Newton's third law of motion
13	In a DC motor, what converts electrical energy into mechanical energy?	Armature	Commutator	Field magnet	Brushes
14	Which law governs the force experienced by a current-carrying conductor in a magnetic field?	Ohm's law	Faraday's law	Ampere's law	Lorentz force law
15	In an AC generator, the direction of the induced current changes:	Periodically	Continuously	Irregularly	Never changes
16	What is the secondary coil of a transformer connected to?	A load	A power source	A capacitor	A resistor
17	When a current-carrying conductor is placed in a magnetic field, what force acts on it?	Gravitational force	Electrostatic force	Magnetic force	Nuclear force
18	Electromagnetic induction is the process of:	Generating electricity from chemical reactions	Generating a magnetic field from an electric current	Generating an electric current by changing magnetic flux	Generating heat from electric current
19	In a transformer, the primary coil is connected to an AC voltage source. What role does the primary coil play?	It steps up the voltage	It steps down the voltage	It generates a magnetic field	It transfers electrical energy to the load
20	According to Ampere’s law, the strength of the magnetic field around a straight steady current-carrying wire:	Decreases with increasing current	Increases with increasing current	Remains constant with increasing current	Depends on the material of the wire
21	What is the SI unit of magnetic field strength?	Tesla	Watt	Volt	Ampere
22	Which of the following statements about transformers is true?	Transformers work only with DC voltage sources	Transformers can only increase voltage, not decrease it	Transformers are based on the principle of self-induction	Transformers can change the voltage level of an AC voltage source
23	What is the device used to convert mechanical energy into electrical energy through electromagnetic induction?	Transformer	Capacitor	AC generator	Diode
24	What happens to the current in the secondary coil of a transformer compared to the primary coil when the voltage is stepped up?	The current increases	The current decreases	The current remains the same	The current becomes zero
25	What happens to the force experienced by a current-carrying conductor placed in a magnetic field if the current direction is reversed?	The force remains the same	The force increases	The force decreases	The force changes direction
26	What component of an AC generator is responsible for generating a changing magnetic field?	Armature	Commutator	Stator	Rotor
27	According to Faraday’s law of electromagnetic induction, the magnitude of the induced electromotive force (emf) is proportional to:	The rate of change of magnetic flux	The resistance of the circuit	The size of the conductor	The strength of the magnetic field
28	What is the primary source of energy that drives an AC generator?	Mechanical energy	Electrical energy	Chemical energy	Nuclear energy
29	What is mutual induction?	The induction of an electromotive force in a circuit by the changing magnetic flux produced by a nearby circuit	The induction of an electric field in a conductor due to its motion through a magnetic field	The production of a magnetic field due to the flow of electric current in a conductor	The production of an electric field due to the presence of nearby charges