Two carbon discs of 1.0 g each are 1.0 cm apart have equal and opposite charges

PHYSICS · Subjective · CBSE · Physics · Electric Charges and Fields · Electric Charges and Fields

Problem

Two carbon discs of 1.0 g each are 1.0 cm apart have equal and opposite charges. If forces of attraction between them is

1.00 \times 10^{-5} \text{ N}

, calculate the ratio of excess electrons to total atoms on the negatively charged disc. (Permittivity constant is

9.0 \times 10^9 \text{ N m}^2 \text{ C}^{-2}

)