Consider a coin, It is electrically neutral and contains equal amounts of positive and negative charge of magnitude 34.8 kC. Suppose that these equal charges were concentrated in two point charges separated by
(i) 1cm `(~(1)/(2)xx`diagonal of the one paisa coin`)`
(ii) 100 m (~length of a long building)
(iii) `10^(6)m` (radius of the earth). find the force on each such point charge in each of the three cases. what do you conclude from these results?

Explanation

Here, `q = +- 3.48 KC = +- 3.48xx10^(4) C, r_(1) = 1 cm = 10^(-2) m, r_(2) = 100m , r_(3) = 10^(6) m, F_(1) = ?, F_(2) = ? , F_(3) = ?`
According to Coulomb's law,
`F_(1) = (|q|^(2))/(4pi in_(0) r_(1)^(2)) = (9xx10^(9)(3.48xx10^(4))^(2))/((10^(-2))^(2)) = 1.09xx10^(23) N`,
`F_(2) = (|q|^(2))/(4pi in_(0) r_(2)^(2)) = (9xx10^(9)(3.48xx10^(4))^(2))/((100)^(2)) = 1.09xx10^(15) N`,
`F_(3) = (|q|^(2))/(4pi in_(0) r_(3)^(2)) = (9xx10^(9)(3.48xx10^(4))^(2))/((10^(6))^(2)) = 1.09xx10^(7) N`
We observe that when `+-` charges in ordinary neutral matter are separated as point charges, they exert an enomous force. Hence , it is not easy to disturb electrical neutrally of matter.