hree different long thin lines of matter containing charges: I. a copper wire carrying an electric current, II. a long amber rod that has been rubbed with fur and has a uniform excess of negative charge, and III. a beam of electrons passing through a vacuum inside a cathode ray tube. They are represented schematically in the figure below. The direction of the electric current and of the electron flow are from left to right. A location marked x is indicated on the diagram and a set of directions with labels are shown at the right