Electric Charges and Fields

Charge $$q_1 = + 2.0 n C $$ is on $$Y-$$ axis at $$y = +2 cm$$ and charge $$q_2 = -2.0 nC$$ is on $$Y-$$ axis at $$y = -2 cm $$ . The force on a test charge $$q_0 = 1 \mu C $$ placed on $$X-$$ axis at $$x= 2 cm $$ is :
A charge $$Q$$ is uniformly distributed over a large plastic plate. The electric field at a point $$P$$ close to the centre of the plate is $$10 V m^{-1} $$ . If the plastic plate is replaced by a copper plate of the same geometrical dimensions and carrying the same charge $$Q$$ , the electric field at the point $$P$$ will become.

Three charges -$$q_{1}$$, +$$q_{2}$$ and -$$q_{3}$$ are placed as shown in the figure. The x-component of the force on -$$q_{1}$$ is proportional to: 

Draw the graphs $$ E \quad Vs \quad r $$ in the following case :
A point charge $$q$$ is placed at  the origin. How does the electric field due to the charge vary with distance $$r$$ from the origin?
The force between two charges 0.06 m apart is $$5\ N$$. If each charge is moved towards the other by $$0.01\ m$$, then the force between them will become