in cathode ray experiment cathode ray behave like negatively charged particles but negatively charged particles is always electron only so why did they say that

The Cathode Ray Experiment, conducted by J.J. Thomson in 1897, was a pivotal experiment in discovering the electron. Here's a step-by-step explanation to your question:

1. In the Cathode Ray Experiment, a high voltage was applied across electrodes in a glass tube that was partially evacuated. This caused a stream of particles to move from the cathode (negative electrode) to the anode (positive electrode). These particles were named "cathode rays".

2. The behavior of these cathode rays in the presence of electric and magnetic fields suggested that they were negatively charged. For example, they were deflected towards the positive plate in an electric field, which is characteristic of negatively charged particles.

3. At the time of this experiment, the concept of an "electron" as we know it today did not exist. The term "electron" was coined after the experiment to describe these negatively charged particles.

4. Therefore, while it's true that all electrons are negatively charged particles, not all negatively charged particles were known to be electrons at the time of the Cathode Ray Experiment. The experiment was a crucial step in identifying the electron as a fundamental particle.

5. So, when they said that the cathode rays behaved like negatively charged particles, they were describing their observations. The identification of these particles as electrons came later.