An infinitely long straight conductor carries a current of $5 \,\mathrm{~A}$ as shown. An electron is moving with a speed of $10^{5} \, \mathrm{~m} / \mathrm{s}$ parallel to the conductor. The perpendicular distance between the electron and the conductor is $20 \, \mathrm{~cm}$ at an instant. Calculate the magnitude of the force experienced by the electron at that instant in $\times 10^{-20} \,N$
  • A$4$
  • B$8 \pi$
  • C$4 \pi$
  • D$8$
NEET 2021, Medium
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