| The story so far | Early discoveries | Two schools of thought | Summary of debate | Exercise |  

Particles or waves?

Early discoveries

Watch the following videos that outline the work of early researchers in this field. The first video discusses the scientific method and how this method is demonstrated by the discovery of cathode rays. It also begins the story of the discoveries of the two schools of thought. The second video further outlines the results of the scientists. Make your own summary as you watch the videos.

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History of cathode rays: part 1 (Running time 3:09)

History of cathode rays: part 2 (Running time 1:30)

A screen grab showing four German scientists.

The following timeline summarises the progress of thought that occurred during this exciting time.

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Timeline for the history of cathode rays

More information on the two schools of thought follows.