To measure a magnetic field between the magnetic poles of a loudspeaker, a small coil having $30$ turns and $2.5 \, cm^2$ area is placed perpendicular to the field and removed immediately. If the total charge flown through the coil is $7.5 \times 10^{-3} \, C$ and the total resistance of the wire and galvanometer is $0.3 \, \Omega$, then the magnitude of the magnetic field is

  • A
    $0.03 \, T$
  • B
    $0.3 \, T$
  • C
    $3 \, T$
  • D
    $3 \times 10^2 \, T$

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