cathode ray

A cathode ray is a stream of tiny particles called electrons that flow through a vacuum, produced when the cathode (a negatively charged electrode) emits electrons. These rays travel in straight lines and can be directed using electric or magnetic fields. When they strike certain materials, they produce effects like fluorescence or deflect toward positive charges. Cathode rays were key in discovering the electron and understanding atomic structure, playing a vital role in the development of electronic technology. They demonstrate how electrically charged particles move and interact in a controlled environment.