The distance between two negatively charged dust particles is 1mm and they repel each other with a force of 4.0*10^-5 N. If the charge on one particle is 4times that of the other, then find out the number of electrons charging them separately. The charge on electron is (5/3)*10^-19 C.

Using the concept of Coulombian force, calculate the magnitude of charge
b. In the second case, assume the charge to be 'q' and '4q' and calculate the force between these for the same distance placement.
c. Put both the forces equal to each other and calculate the value of charge and equate it according to the concept of 'quantizitaion of charge'.
You will get the val;ue of no. of charge transferred .

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