Given below are two statement , one is labelled as Assertion A and the other is labelled as Reason R .
Assertion A : The diameter of colloidaparticles in solution should not be much smaller than wavelength of light to show Tyndall effect .
Reason R : The light scatters inall directions when the size of particles is large enough.
In the light of the above statements, choose the correct answer from the options given below :

Options

A. A is false but R is true
B. A is true but R is false
C. Both A and R are correct R is NOT the correct explanation of A
D. Both A and R are correct R is the correct explanation of A

Answer

To solve the question regarding the Assertion A and Reason R, we will analyze both statements step by step.

### Step 1: Analyze Assertion A
**Assertion A** states: "The diameter of colloidal particles in solution should not be much smaller than the wavelength of light to show Tyndall effect."

- The Tyndall effect is the scattering of light by colloidal particles. For this effect to be observed, the size of the colloidal particles should be comparable to the wavelength of light (approximately 400 nm to 700 nm for visible light).
- If the particles are much smaller than the wavelength of light, they will not scatter light effectively, and the Tyndall effect will not be observed.

**Conclusion for Assertion A**: This statement is **correct**.

### Step 2: Analyze Reason R
**Reason R** states: "The light scatters in all directions when the size of the particles is large enough."

- When the size of the particles is large enough (typically larger than the wavelength of light), they can scatter light in all directions. This is a fundamental principle of light scattering.
- This scattering is what contributes to the visibility of the Tyndall effect, as larger particles can effectively scatter light.

**Conclusion for Reason R**: This statement is also **correct**.

### Step 3: Determine the relationship between Assertion A and Reason R
- Both Assertion A and Reason R are correct.
- Furthermore, Reason R provides a correct explanation for Assertion A, as it explains why the size of colloidal particles affects the visibility of the Tyndall effect.

### Final Conclusion
Both Assertion A and Reason R are correct, and Reason R is the correct explanation of Assertion A.

### Answer
The correct option is: **Both assertion and reason are correct, and reason is the correct explanation of assertion.**

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