Chapter 28, Problem 9P

ILW In Fig. 28-32, an electron accelerated from rest through potential difference V₁ = 1.00 kV enters the gap between two parallel plates having separation d = 20.0 mm potential difference V₂ = 100 V. The lower plate is at the lower potential. Neglect fringing and assume that the electron’s velocity vector is perpendicular to the electric field vector between the plates. In unit-vector notation, what uniform magnetic field allows the electron to travel in a straight line in the gap?

Figure 28-32 Question 9.