Two point charges of $40 \ \mu C$ and $-20 \ \mu C$ are placed at a certain distance. If they are brought into contact and then placed at the same distance,what is the ratio of the electrostatic force in the two cases?

  • A
    $8:1$
  • B
    $4:1$
  • C
    $1:8$
  • D
    $1:1$

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