The charge on two particles A and B at rest is q on each The direction of motion of a charged particle c placed at a point on the straight line joining thee two charges depend on

Dear pallavi

Case 1 : particle c is in etween A and B and positively charged

if the placed charged partcle is positive charged then particle at A and B repel the charge at c .if the c particle is near to particle A ,then Repulsion force by A is more than B so particle start moving towards B .when it cross the midddle position then repulsion force  by B will be more and after some time particle C will start movieng A so particle C execute  periodic motion between A and B

case 2 particle c is in etween A and B and negatively charged

 both particle A and B attract particle C ,so particle C will move to those particle which is nearer to it.

case 3  particle C is not placed between the A and B

   if  C is negative it will move towads the  charge A and B ,

  if C is positive then it will move away from the chage And B

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