Scattering of light by colloidal particles is known as

Options

A. Tyndall effect
B. Brownian motion
C. reflection
D. rectilinear propagation

Explanation

To answer the question "Scattering of light by colloidal particles is known as," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Colloidal Particles**:
- Colloidal particles are small particles that are suspended in a medium (liquid or gas). Their size typically ranges from 1 to 1000 nanometers.

2. **Behavior of Light in Colloidal Solutions**:
- When light passes through a colloidal solution, the colloidal particles interact with the light. Due to their size, they can scatter the light in different directions.

3. **Identifying the Phenomenon**:
- The scattering of light by these colloidal particles is a specific phenomenon that occurs due to their size and the nature of the medium they are in.

4. **Naming the Phenomenon**:
- This phenomenon of light scattering by colloidal particles is known as the **Tyndall Effect**.

5. **Conclusion**:
- Therefore, the correct answer to the question is that the scattering of light by colloidal particles is known as the **Tyndall Effect**.

### Final Answer:
Scattering of light by colloidal particles is known as the **Tyndall Effect**.

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