The current $I$ in the wire is now changed while the angle $\theta$ remains constant. On Fig. 6.2, sketch a graph to show how the force $F$ on the wire varies with current $I$.
The angle $\theta$ between the wire and the magnetic field is now changed, while the current $I$ is kept constant. On Fig. 6.3, sketch a graph to show how the force $F$ on the wire varies with angle $\theta$.
As shown in Fig. 6.4, a uniform magnetic field is at right-angles to the rectangular surface PQRS of a slice of conducting material. Electrons travel towards side SR and enter the slice of conducting material. They enter at right-angles to side SR.
Explain why, at first, the electrons do not move in straight lines across the slice from side SR to side PQ.
Explain to which side, PS or QR, the electrons are deflected.