The earth's magnetic induction at a certain point is $7 \times {10^{ - 5}}\,Wb/{m^2}.$ This is to be annulled by the magnetic induction at the centre of a circular conducting loop of radius $5 \,cm$. The required current in the loop is......$A$
  • A$0.56$
  • B$5.6$
  • C$0.28$
  • D$2.8$
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