Question

Figure shows two large plates $P_1$ and $P_2$ tightly held against each other and placed between two equal and unlike point charges perpendicular o to the line joining them,
i. What will happen o the plates when they are released?
ii. Draw the pattern of the electric field lines for the system.

Answer 1

(i) Charges induced on outer surfaces of $P_1$ and $P_2$ are $-Q$ and $+Q$ respectively. When plates are released, they will tend to move away from one another; plate $P_1$ moving towards $+Q$ and $P_2$ towards $-Q$ due to attraction.
(ii) The field pattern is shown in fig.