a. A beam of electrons is sent horizontally down the axis of…

a. A beam of electrons is sent horizontally down the axis of a tube to strike a fluorescent screen at the end of the tube. On the way, the electrons encounter a magnetic field directed vertically downward. How will the spot on the screen will be deflected? Explain with reasoning. (4 pts) b. An electron is moving at 2.5×106 m/s perpendicular to a 3.5 mT magnetic field. What is the radius of its path?  (e = 1.6×10-19 C, me = 9.1×10-31 kg)  (6 pts)