1. The magnetic field at the common center due to a current-carrying loop is given by: B = μ0I/2R Let the currents in loops P and Q be Ip and = Iq = 9A, with radii Rp and Rq ​ such that Rp/Rq = 2/3. For zero net magnetic field: Ip/Iq = Rq/Rp = 3/2 ⟹ Ip = 6A To cancel Q’s anticlockwise field, P must carRead more

    The magnetic field at the common center due to a current-carrying loop is given by:
    B = μ0I/2R

    Let the currents in loops P and Q be Ip and = Iq = 9A, with radii Rp and Rq
    ​ such that Rp/Rq = 2/3. For zero net magnetic field:
    Ip/Iq = Rq/Rp = 3/2 ⟹ Ip = 6A To cancel Q’s anticlockwise field,
    P must carry 6 A in the clockwise direction.
    Answer: (D) 6 A in the clockwise direction.

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  2. The magnetic field around a long, straight current-carrying wire is given by: B = μ0I/2πr Substituting values: B = 4π × 10⁻⁷ × 15/2π × 2.5 = 1.2 × 10⁻⁶ T = 1.2 μT Using the right-hand thumb rule, the magnetic field at a point east of the wire points vertically downward. Answer: (A) 1.2 µT, verticallRead more

    The magnetic field around a long, straight current-carrying wire is given by:
    B = μ0I/2πr
    Substituting values:
    B = 4π × 10⁻⁷ × 15/2π × 2.5 = 1.2 × 10⁻⁶ T = 1.2 μT
    Using the right-hand thumb rule, the magnetic field at a point east of the wire points vertically downward.
    Answer: (A) 1.2 µT, vertically downward.

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  3. An ammeter has low internal resistance and is designed to measure current by connecting in series with the circuit. To use it as a voltmeter, a high resistance must be connected in series to limit current and measure potential difference. This combination ensures minimal current through the meter whRead more

    An ammeter has low internal resistance and is designed to measure current by connecting in series with the circuit. To use it as a voltmeter, a high resistance must be connected in series to limit current and measure potential difference. This combination ensures minimal current through the meter while allowing voltage measurement.
    Answer: (D) high resistance in series.
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  4. The force on a current-carrying wire in a magnetic field is given by: F = BILsinθ The force is maximum when sinθ = 1, i.e., = 90° . This means the wire must be perpendicular to the magnetic field to experience the maximum force. Answer: (A) perpendicular to the magnetic field. For more visit here: hRead more

    The force on a current-carrying wire in a magnetic field is given by:
    F = BILsinθ

    The force is maximum when sinθ = 1, i.e., = 90°
    . This means the wire must be perpendicular to the magnetic field to experience the maximum force.
    Answer: (A) perpendicular to the magnetic field.

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  5. To remove tension in the strings, the magnetic force must balance the gravitational force: Bil = mg Rearranging for current I: I = mg/BL Thus, the magnitude of current needed to make the net force zero is: I = mg/BL Answer: (C) mg/IB For more visit here: https://www.tiwariacademy.com/ncert-solutionsRead more

    To remove tension in the strings, the magnetic force must balance the gravitational force:
    Bil = mg
    Rearranging for current I:
    I = mg/BL
    Thus, the magnitude of current needed to make the net force zero is:
    I = mg/BL
    Answer: (C) mg/IB

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