One of the two small circular coils, (none of them having any self- inductance) is suspended with a $V-$ shaped copper wire, with plane horizontal. The other coil is placed just below the first one with plane horizontal. Both the coils are connected in series with a $dc$ supply. The coils are found to attract each other with a force. Which one of the following statements is incorrect ?
  • A
    Both the coils carry currents in the same direction
  • B
    Coils will attract each other, even if the supply is an ac source
  • CForce is proportional to $d^{-1}$
  • DForce is proportional to $d^{-2}$
JEE MAIN 2013, Diffcult
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