The distance between charges 5×10−11C and −2.7×10−11C is 0.2m. The distance at which a third charge should be placed in order that it will not experience any force along the line joining the two charges is
If two opposite charges are separated by a certain distance, then for it's equalibrium a third
charge should be kept outside and near the charge which is smaller in magnitude.
Here, suppose third charge q is placed at a distance x from −2.7×10−11C then for it's
equalibrium |F1|=|F2|
⇒ KQ1q(x+0.2)2=KQ2qx2⇒ x=0.556 m
(Here K=14πϵ0 and Q1=5×10−11C, Q2=−2.7×10−11C)