A : Amorphous solids are isotropic.
R : Amorphous solids are not rigid.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To analyze the statements given in the question, we will break down the concepts of amorphous solids, their isotropic nature, and rigidity step by step.

### Step 1: Understanding Amorphous Solids
- Amorphous solids are materials that do not have a long-range order in their atomic arrangement. Unlike crystalline solids, which have a regular and repeating structure, amorphous solids have a disordered arrangement of particles.

**Hint:** Remember that the lack of long-range order is a key characteristic of amorphous solids.

### Step 2: Isotropic Nature of Amorphous Solids
- The first statement (A) claims that amorphous solids are isotropic. Isotropic materials have the same physical properties in all directions. This is true for amorphous solids because their short-range order leads to uniformity in properties like refractive index, thermal conductivity, etc., regardless of the direction in which they are measured.

**Hint:** Isotropic means uniform properties in all directions; think of how glass behaves.

### Step 3: Rigidity of Amorphous Solids
- The second statement (R) states that amorphous solids are not rigid. This is also true; amorphous solids tend to be softer and more flexible than crystalline solids due to the weaker intermolecular forces and the lack of a defined structure.

**Hint:** Consider how materials like glass can be shaped and molded compared to rigid crystals.

### Step 4: Evaluating the Relationship Between A and R
- While both statements A and R are true, the reason (R) does not explain why amorphous solids are isotropic (A). The isotropic nature stems from their short-range order, not directly from their rigidity or softness.

**Hint:** Just because both statements are true does not mean one explains the other; focus on the relationship between them.

### Conclusion
- Therefore, the answer to the question is that both statements are true, but the reason provided does not correctly explain the first statement.

**Final Answer:** A is true, R is true, but R is not the correct explanation for A.