Define the term electric field.
Fig. 5.1 shows two parallel conducting plates in a vacuum. The plates are separated by $6.7\,\text{cm}$ and there is a potential difference (p.d.) of $430\,\text{V}$ across them.
On Fig. 5.1, add four field lines to show the electric field between the plates.
Determine the strength $E$ of the electric field between the plates.
An electron moves at a speed of $2.6 \times 10^{7}\,\text{m s}^{-1}$ towards the region between the plates, as shown in Fig. 5.1. On Fig. 5.1, draw the electron’s path as it travels between and beyond the plates.
A uniform magnetic field is now applied in the region of the electric field in Fig. 5.1, so that the electron in (b)(iii) travels undeviated through the region.
Determine which way the uniform magnetic field is directed.
Explain, with reference to the forces produced by the two fields on the electron, why the path of the electron is undeviated.
Determine the flux density $B$ of the uniform magnetic field. Include a unit with your answer.