Chapter 28, Problem 30P

GO In Fig. 28-40. an electron with an initial kinetic energy of 4.0 keV enters region 1 al time t = 0. That region contains a uniform magnetic field directed into the page, with magnitude 0.010 T. The electron goes through a half-circle and then exits region 1, headed toward region 2 across a gap of 25.0 cm. There is an electric potential difference ΔV = 2000 V across the gap with a polarity such that the electron's speed increases uniformly as it traverses the gap Region 2 contains, a uniform magnetic field directed out of the page, with magnitude 0.020 T. The electron goes through a half-circle and then leaves region 2. At what time t does it leave?

Figure 28-40 Problem 30.