What is the behaviour of cathode rays in the presence of an electric field?

Answer

To understand the behavior of cathode rays in the presence of an electric field, we can break down the explanation into clear steps:

### Step-by-Step Solution:

1. **Definition of Cathode Rays**:
- Cathode rays are streams of electrons emitted from the cathode (negative electrode) in a vacuum tube.

2. **Charge of Cathode Rays**:
- Cathode rays are negatively charged because they consist of electrons, which carry a negative charge.

3. **Presence of Electric Field**:
- An electric field is created between two plates, one positively charged and the other negatively charged.

4. **Interaction with Electric Field**:
- When cathode rays (negatively charged electrons) enter the electric field, they experience a force due to the electric field.

5. **Direction of Deflection**:
- Since cathode rays are negatively charged, they will be attracted towards the positively charged plate and repelled by the negatively charged plate.

6. **Resulting Behavior**:
- As a result, cathode rays will be deflected towards the positive plate when subjected to an electric field.

7. **Conclusion**:
- The behavior of cathode rays in an electric field demonstrates that they are negatively charged particles, as they move towards the positive charge.

### Summary:
In summary, cathode rays, being negatively charged, are deflected towards the positive plate in the presence of an electric field.

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