Cathode rays are made up of

Options

A. positively charged particles
B. negatively charged particles
C. neutral particles
D. none of these.

Explanation

**Step-by-Step Solution:**

1. **Understanding Cathode Rays**: Cathode rays are streams of particles that are emitted from the cathode (the negative electrode) in a vacuum tube when a high voltage is applied.

2. **Observation of the Experiment**: In a cathode ray discharge tube, when voltage is applied, a green glow is observed. This glow indicates the presence of particles moving from the cathode to the anode.

3. **Determining the Charge**: The anode is positively charged, and since opposite charges attract, the particles that are emitted from the cathode must be negatively charged.

4. **Identification of Cathode Rays**: The particles that make up cathode rays are identified as electrons, which are negatively charged subatomic particles.

5. **Conclusion**: Therefore, cathode rays are made up of negatively charged particles, specifically electrons.

**Final Answer**: Cathode rays are made up of negatively charged particles (electrons).

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