Plot a graph showing the variation of coulomb force (F) versus `((1)/(r^(2)))`, where r is the distance between the two charges of each pair of charges:
`(1mu C,2mu C) and (2muC-3muC)`. Interpet the graphs obtained.

Explanation

According to Coulomb's law,
`F oo q_(1) q_(2)` and `F = oo (1)/(r^(2))`
Therefore, both pairs of charges graph between
F and `(1)/(r^(2))` is a straight line. Between `(1 mu C, 2 muC)`, force is positive/ repulsive and proportional to `1 (2) = 2`. Between `(2 muC and -3 muC)` force is negative/ attractive and proportional to `2 (3) = 6`
Therefore, in Fig 1(a).25, OA represents the variation between F and `l//r^(2)` for the pair `(1 mu C, 2mu C)` And ,OB represents the variation between F and `l//r^(2)` for the secound pair `(2 muC, -3 muC)`.