A cathode ray is a stream of electrons that are emitted from the cathode of a cathode ray tube (CRT) and travel towards the anode. These electrons are accelerated by an electric field and then pass through a small aperture before striking a phosphor-coated screen, causing it to emit light. The process of cathode rays being emitted, accelerated and striking a phosphor-coated screen to produce light is known as cathode ray tube.
On the other hand, a normal light ray refers to the propagation of light through a medium, such as air or glass. Light is a type of electromagnetic wave that is made up of oscillating electric and magnetic fields. These fields oscillate perpendicular to each other and to the direction of propagation. Light can be produced by various sources, such as the sun, incandescent bulbs, and LED lights.
In summary, a cathode ray is a stream of electrons emitted from a cathode, while a normal light ray is a type of electromagnetic wave that is produced by various sources. The main difference between the two is that cathode rays are made up of electrons, while light rays are made up of oscillating electric and magnetic fields. Additionally, cathode rays are produced and used in cathode ray tube and other electronic devices, while light rays are present in our everyday life and used in various applications such as lighting, communication, and photography.