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AP EAMCET202018 Sep 2020Morning ShiftPhysicsElectrostaticsActual

Three charges (4 q, Q ) and (q ) are placed at positions (0, l 2 ) and (l ) respectively along a straight line. If the resultant force on (q ) is zero, then (Q ) is equal to

Options

  1. A(-q )
  2. B(-2 q )
  3. C(- q 2 )
  4. D(4 q t )

Correct answer

A. (-q )

Step-by-step solution

The given arrangement of charges is shown in following figure, Resultant force on charge (q ) is zero. ( aligned & i.e., K 4 q q l^2 + K Q q (l / 2)^2 =0 & 4 q l^2 + 4 Q l^2 =0 & q+Q=0 & Q=-q aligned )

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