Q.

A positive ion A and a negative ion B has charges 6.67×1019 C and 9.6×1010 C, and masses 19.2×1027 kg and 9×1027 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 P×1013, where the value of P is __________.

Take 14πε0=9×109 Nm2C1 and universal gravitational constant as 6.67×1011 Nm2 kg2)          [2025]


Ans.

(Bonus)

 Fe=kq1q2r2 and Fg=Gm1m2r2

FeFg=kq1q2Gm1m2

      =9×109×6.67×1019×9.6×10106.67×1011×19.2×1027×9×1027

      =10202×1065=12×1045