A positive ion A and a negative ion B has charges 6.67 × 10^-19 C and 9.6 × 10^-10 C, and masses 19.2 × 10^-27 kg and 9 × 10^-27 kg respectively. At…

A positive ion A and a negative ion B has charges $\displaystyle 6.67 \times 10^{-19} \mathrm{C}$ and $\displaystyle 9.6 \times 10^{-10} \mathrm{C}$, and masses $\displaystyle 19.2 \times 10^{-27} \mathrm{~kg}$ and $\displaystyle 9 \times 10^{-27} \mathrm{~kg}$ respectively. At an instant, the ions are separated by a certain distance r . At that instant the ratio of the magnitudes of electrostatic force to gravitational force is $\displaystyle \mathrm{P} \times 10^{-13}$, where the value of P is $\displaystyle \_\_\_\_$. (Take $\displaystyle \frac{1}{4 \pi \varepsilon_0}=9 \times 10^9 \mathrm{Nm}^2 \mathrm{C}^{-1}$ and universal gravitational constant as $\displaystyle 6.67 \times 10^{-11} \mathrm{Nm}^2 \mathrm{~kg}^{-2}$ )