A positively charged particle moves through a region with a uniform electric field pointing toward the top of the page and a uniform magnetic field pointing into the page. The particle can have one of the four velocities shown in the figure.
(a) Rank the four possibilities in order of increasing magnitude of the net force the particle experiences. Indicate ties where appropriate. (Use only the symbols F1, F2, F3, F4, <, and =, for example F1 < F2 = F3.)
(b) Which of the four velocities could potentially result in zero net force? (Select all that apply.)
