Two point charges `q_(A) = 3 mu C` and `q_(B) = -3 muC` are located 20 cm apart in vaccum (a) what is the electric field at the mid point O of the line AB joining the two charges ? (b) If a negative test charge of magnitude `1.5xx10^(-9) C` is placed at the point, what is the force experienced by the test charge ?

Explanation

(a) `5.4 xx10^(6) NC^(-1)` along OB
(b) `8.1 xx10^(-3) N` along OA