The charges on two sphere are +7μC and – 5μC respectively. They experience a force F. If each of them is given and additional charge of – 2μC, the new force of attraction will be

$F = \frac{1}{4 {πε}_{0}} \frac{(+ 7 \times 10^{- 6}) (- 5 \times 10^{- 6})}{r^{2}} = - \frac{1}{4 {πε}_{0}} \frac{35 \times 10^{12}}{r^{2}} N$

$F' = \frac{1}{4 {πε}_{0}} \frac{(+ 5 \times 10^{- 6}) (- 7 \times 10^{- 6})}{r^{2}} = - \frac{1}{4 {πε}_{0}} \frac{35 \times 10^{12}}{r^{2}} N$

The charges on two sphere are +7 $μ$ C and – 5 $μ$ C respectively. They experience a force F. If each of them is given and additional charge of – 2 $μ$ C, the new force of attraction will be