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Peak or instantaneous emf of a coil rotating in a uniform field

This type of question, asked 7 times: 2021 Paper 19, 14 Jun 2022, 30 Jan 2023, 1 Feb 2023, 1 Feb 2024, 29 Jan 2025, 22 Jan 2026 S2. All 7 questions below, oldest first.

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  1. Question 1

    2021 Paper 19

    25
    A circular coil of radius 8.0 cm8.0\text{ }cm and 20 turns is rotated about its vertical diameter with an angular speed of 50rads−150rads^{- 1} in a uniform horizontal magnetic field of 3.0×10−2 T3.0 \times10^{- 2}\text{ }T. The maximum emf induced in the coil will be ______ ×10−2\times10^{- 2} volt (rounded off to the nearest integer)

  2. Question 2

    14 Jun 2022

    118
    A circular coil of 1000 turns each with area 1 m21{\text{ }m}^{2} is rotated about its vertical diameter at the rate of one revolution per second in a uniform horizontal magnetic field of 0.07 T0.07\text{ }T. The maximum voltage generated will be ____\_\_\_\_ V.

  3. Question 3

    30 Jan 2023

    116
    In an ac generator, a rectangular coil of 100 turns each having area 14×10−2 m214 \times10^{- 2}{\text{ }m}^{2} is rotated at 360rev/min about an axis perpendicular to a uniform magnetic field of magnitude 3.0 T3.0\text{ }T. The maximum value of the emf produced will be ____\_\_\_\_ V. (Take π=227\pi = \frac{22}{7})

  4. Question 4

    1 Feb 2023

    112
    A square shaped coil of area 70 cm270{\text{ }cm}^{2} having 600 turns rotates in a magnetic field of 0.4wbm−20.4wbm^{- 2}, about an axis which is parallel to one of the side of the coil and perpendicular to the direction of field. If the coil completes 500 revolution in a minute, the instantaneous emf when the plane of the coil is inclined at 60∘60^{\circ} with the field, will be ____\_\_\_\_ V. (Take π=227\pi=\frac{22}{7} )

  5. Question 5

    1 Feb 2024

    117
    A coil of 200 turns and area 0.20 m20.20{\text{ }m}^{2} is rotated at half a revolution per second and is placed in uniform magnetic field of 0.01 T0.01\text{ }T perpendicular to axis of rotation of the coil. The maximum voltage generated in the coil is 2πβ\frac{2\pi}{\beta} volt. The value of β\beta is______

  6. Question 6

    29 Jan 2025

    12
    A coil of area A and N turns is rotating with angular velocity ω\omega in a uniform magnetic field B→\overrightarrow{B} about an axis perpendicular to B→\overrightarrow{B}. Magnetic flux φ\varphi and induced emf ε\varepsilon across it, at an instant when B→\overrightarrow{B} is parallel to the plane of coil, are :

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  7. Question 7

    22 Jan 2026 S2

    21
    A conducting circular loop is rotated about its diameter at a constant angular speed of 100rad/s100rad/s in a magnetic field of 0.5 T perpendicular to the axis of rotation. When the loop is rotated by 30∘30^{\circ} from the horizontal position, the induced EMF is 15.4 mV . The radius of the loop is ____\_\_\_\_ mm .  (Take π=227)\left. \ (Take\ \pi = \frac{22}{7} \right)