1. The voltage sensitivity of a galvanometer is given by: Voltage Sensitivity = Current Sensitivity/R If current sensitivity increases by 20% and resistance increases by 25%, the net change in voltage sensitivity is: 1.2/1.25 = 0.96 This indicates a 4% decrease in voltage sensitivity. Answer: (D) DecreRead more

    The voltage sensitivity of a galvanometer is given by:
    Voltage Sensitivity = Current Sensitivity/R
    If current sensitivity increases by 20% and resistance increases by 25%, the net change in voltage sensitivity is:
    1.2/1.25 = 0.96
    This indicates a 4% decrease in voltage sensitivity.
    Answer: (D) Decrease by 4%.

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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 × 5/2π × 0.10 = 1 × 10⁻⁵ T Using the right-hand thumb rule, the magnetic field at a point due south acts upward. Therefore, the correct answer is: (B) 1 × 10⁻⁵ T acting upwarRead more

    The magnetic field around a long, straight current-carrying wire is given by:

    B = μ0I/2πr

    ​Substituting values:
    B = 4π × 10⁻⁷ × 5/2π × 0.10 = 1 × 10⁻⁵ T
    Using the right-hand thumb rule, the magnetic field at a point due south acts upward. Therefore, the correct answer is:
    (B) 1 × 10⁻⁵ T acting upwards.

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  3. An α-particle projected along the Y-axis with velocity v in the presence of uniform electric and magnetic fields along the X-axis experiences a magnetic force perpendicular to both velocity and magnetic field, causing circular motion in the YZ plane. The electric field imparts acceleration along theRead more

    An α-particle projected along the Y-axis with velocity
    v in the presence of uniform electric and magnetic fields along the X-axis experiences a magnetic force perpendicular to both velocity and magnetic field, causing circular motion in the YZ plane. The electric field imparts acceleration along the X-axis, resulting in a helical trajectory with its axis parallel to the X-axis.
    Answer: (C) Helical with its axis parallel to X-axis.

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  4. The magnetic field around a long, straight current-carrying wire is given by Ampere’s circuital law as: B = μ0​I/2πr .Here: μ0 4π × 10⁻⁷Tm/A (permeability of free space) I =10 A (current) r = 0.10m (distance) Substituting values: B = 4π × 10⁻⁷× 10/2π × 0.10 = 2 × 10⁻⁵T To determine the direction ofRead more

    The magnetic field around a long, straight current-carrying wire is given by Ampere’s circuital law as:
    B = μ0​I/2πr
    .Here:
    μ0 4π × 10⁻⁷Tm/A (permeability of free space)
    I =10 A (current) r = 0.10m (distance)
    Substituting values:
    B = 4π × 10⁻⁷× 10/2π × 0.10 = 2 × 10⁻⁵T
    To determine the direction of the magnetic field, use the right-hand thumb rule: Point the thumb in the direction of current (east to west) and curl the fingers around the wire. At a point due north, the magnetic field points downward. Hence, the correct answer is:
    (A) 2 × 10⁻⁵ T, acting downwards.

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