An aeroplane, with its wings spread $10 \mathrm{m},$ is flying at a speed of $180 \mathrm{km} {\mathrm{h}}^{-1}$ in a horizontal direction. The total intensity of earth's field at that part is $2.5\times {10}^{-4} \mathrm{Wb} {\mathrm{m}}^{-2}$ and the angle of dip is $60°.$ The emf induced between the tips of the plane wings will be

• Correct answer
  A

  $108.25 \mathrm{mV}$
• B

  $54.125 \mathrm{mV}$
• C

  $88.37 \mathrm{mV}$
• D

  $62.50 \mathrm{mV}$

Hence, the correct answer is option: 'A'.