State the meaning of an electric field.
On Fig. 5.1, place $(+)$ or $(-)$ next to each sphere to indicate its charge.
On Fig. 5.1, identify a region where the electric field magnitude is (1) constant, and label it $C$, and (2) decreasing, and label it $D$.
Fig. 5.1 shows the electric field between an earthed metal plate and two charged metal spheres.
On Fig. 5.1, mark a region where the electric field magnitude is constant, and label it C.
On Fig. 5.1, mark a region where the electric field magnitude is decreasing, and label it D.
As shown in Fig. 5.2, a molecule has its centre P of positive charge a distance of $2.8 \times 10^{-10}\,\text{m}$ from its centre N of negative charge. The molecule is placed in a uniform electric field of field strength $5.0 \times 10^{4}\,\text{V m}^{-1}$. The axis NP of the molecule makes an angle of $30^\circ$ with this uniform applied electric field. The magnitude of the charge at P and at N is $1.6 \times 10^{-19}\,\text{C}$.
On Fig. 5.2, draw an arrow at P and another at N to show the directions of the forces due to the applied electric field at each point.
Calculate the torque on the molecule due to the forces in (i).