Chapter 4: Moving Charges and Magnetism Assertion Reason
These questions of two statements each, printed as Assertion and Reason. While answering these Questions you are required to choose any one of the following four responses.
(A) If both Assertion & Reason are true & the Reason is a correct explanation of the Assertion.
(B) If both Assertion and Reason are true but Reason is not a correct explanation of the Assertion.
(C) If Assertion is true but the Reason is false.
(D) If Assertion & Reason both are false.
Q.1 Assertion : The ferromagnetic substance do not obey Curie’s law.
Reason : At Curie point a ferromagnetic substance start behaving as a paramagnetic substance.
(1) A (2) B (3) C (4) D
Answer: 2
Q.2 Assertion : The properties of paramagnetic and ferromagnetic substance are not effected by heating.
Reason : As temperature rises, the alignment of molecular magnets gradually decreases.
(1) A (2) B (3) C (4) D
Answer: 4
Q.3 Assertion : Soft iron is used as transformer core.
Reason : Soft iron has narrow hysteresis loop.
(1) A (2) B (3) C (4) D
Answer: 1
Q.4 Assertion : The susceptibility of diamagnetic materials does not depend upon temperature.
Reason : Every atom of a diamagnetic material is not a complete magnet in itself.
(1) A (2) B (3) C (4) D
Answer: 3
Q.5 Assertion : For a perfectly diamagnetic substance permeability is always one.
Reason : The ability of a material of permit the passage of magnetic lines of force through it is called magnetic permeability is always one.
(1) A (2) B (3) C (4) D
Answer: 4
Q.6 Assertion : For making permanent magnets, steel is referred over soft iron.
Reason : As retentivity of steel is smaller.
(1) A (2) B (3) C (4) D
Answer: 3
Q.7 Assertion : Diamagnetic materials can exhibit magnetism.
Reason : Diamagnetic materials have permanent magnetic dipole moment.
(1) A (2) B (3) C (4) D
Answer: 3
Assertion-Reason Questions
- Assertion (A): A current-carrying conductor produces a magnetic field around it.
Reason (R): Moving charges produce a magnetic field.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The force on a current-carrying conductor in a magnetic field is zero if the conductor is parallel to the field.
Reason (R): The force on the conductor is given by F = I(L × B), which is zero when L is parallel to B.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): A charged particle moving in a magnetic field experiences maximum force when its velocity is perpendicular to the field.
Reason (R): The force on the particle is given by F = q(v × B), which is maximum when v is perpendicular to B.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): A solenoid can be used to create a uniform magnetic field.
Reason (R): The magnetic field inside a long solenoid is uniform and parallel to its axis.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The magnetic field at the center of a circular loop carrying current is zero.
Reason (R): The magnetic field lines due to each segment of the loop cancel out at the center.
Answer: A is false but R is true. - Assertion (A): The magnetic moment of a current loop is proportional to the current and the area of the loop.
Reason (R): The magnetic moment is given by M = I × A, where I is the current and A is the area.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): A moving charge in a uniform magnetic field traces a circular path.
Reason (R): The magnetic force acts as a centripetal force causing circular motion.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The magnetic field inside a toroid is zero.
Reason (R): The magnetic field lines inside a toroid are circular and confined within the core.
Answer: A is false but R is true. - Assertion (A): Two parallel current-carrying conductors attract each other if the currents are in the same direction.
Reason (R): The magnetic field produced by one conductor exerts a force on the other conductor in such a way that they attract each other.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The force on a charged particle moving in a magnetic field is independent of the velocity of the particle.
Reason (R): The force on the particle is given by F = q(v × B).
Answer: A is false but R is true. - Assertion (A): The direction of the magnetic field around a straight current-carrying conductor can be determined using the right-hand rule.
Reason (R): The right-hand rule states that if the thumb points in the direction of the current, the curled fingers show the direction of the magnetic field.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): Magnetic field lines form closed loops.
Reason (R): Magnetic monopoles do not exist.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The Biot-Savart law is used to calculate the magnetic field due to a small element of current.
Reason (R): The Biot-Savart law relates the magnetic field to the current element, the distance from the element, and the angle between the element and the line connecting the point of interest.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The magnitude of the magnetic field at a point due to a long straight current-carrying wire decreases with distance from the wire.
Reason (R): The magnetic field due to a long straight wire is inversely proportional to the distance from the wire.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The magnetic field inside a current-carrying solenoid is directly proportional to the current and the number of turns per unit length.
Reason (R): The magnetic field inside a solenoid is given by B = μ₀nI, where n is the number of turns per unit length and I is the current.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The force between two parallel current-carrying conductors can be attractive or repulsive.
Reason (R): The direction of the force depends on whether the currents are in the same or opposite directions.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The magnetic flux through a surface is always zero if the surface is closed.
Reason (R): Magnetic field lines do not begin or end at any point, ensuring that the net flux through a closed surface is zero.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): The SI unit of magnetic field strength is the Tesla.
Reason (R): One Tesla is defined as the magnetic field which exerts a force of one Newton per ampere per meter on a current-carrying conductor.
Answer: Both A and R are true and R is the correct explanation of A. - Assertion (A): A galvanometer can be converted into an ammeter by connecting a high resistance in series.
Reason (R): The series resistance allows the galvanometer to measure higher currents by reducing the overall current flowing through it.
Answer: A is false but R is true. - Assertion (A): Ampere’s circuital law is used to determine the magnetic field due to a given current distribution.
Reason (R): Ampere’s circuital law states that the line integral of the magnetic field around a closed path is proportional to the total current enclosed by the path.
Answer: Both A and R are true and R is the correct explanation of A.
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