At the time that J. J. Thomson conducted his experiments on cathode rays, the nature of the electron was in doubt. Some considered it to be a form of radiation, like light; others believed the electron to be a particle. Some of the observations made on cathode rays were used to advance one view or the other. Explain how each of the following properties of cathode rays supports either the wave or the particle model of the electron.

(a) They pass through metal foils.

(b) They travel at speeds slower than that of light.

(c) If an object is placed in their path, they cast a shadow.

(d) Their path is deflected when they are passed between electrically charged plates.