1. Tardigrade
  2. Question
  3. Physics
  4. Charge Q is divided into two parts which are then kept some distance apart. The force between them will be maximum if the two parts are

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. Charge $Q$ is divided into two parts which are then kept some distance apart. The force between them will be maximum if the two parts are

Electric Charges and Fields

Solution:

$ F=\left(\frac{1}{4 \pi \varepsilon_{0}}\right) \cdot\left(\frac{q( Q -q)}{r^{2}}\right)$
$F$ is maximum, when $q(Q-q)$ is maximum.
$F^{\prime}(q)=Q-2 q$
For maxima, $F^{\prime}(q)=Q-2 q=0$
or $q=\frac{Q}{2}$
$F^{\prime \prime}(q)=-2<0$ (Maxima).