STATEMENT-1 : Infra-red waves are caleld heat-waves.
STATEMENT-2 : Infra-red waves cause the vibration of not only electrons, but entiie or moelcules of a substance.

Options

A. Statement-1 is True, Statement-2 is True-2 is True , Statement-2 is a correct explanation for Statement-5
B. Statement-1 is True, Statement-2 is True-2 is NOT a correct explanation for Statement-5
C. Statement-1 is True Statement-2 is False
D. Statement-1 is False, Statement-2 is True

Answer

To analyze the statements provided in the question, we will break down the reasoning step by step.

### Step 1: Understanding Statement 1
**Statement 1:** Infra-red waves are called heat waves.

**Explanation:** Infrared waves are a type of electromagnetic radiation with wavelengths longer than visible light but shorter than microwaves. They are commonly associated with heat because they can transfer thermal energy. When infrared radiation strikes an object, it is absorbed and causes the object's temperature to rise, which is why they are often referred to as heat waves.

### Step 2: Understanding Statement 2
**Statement 2:** Infra-red waves cause the vibration of not only electrons, but entire molecules of a substance.

**Explanation:** When infrared waves interact with matter, they can indeed cause vibrations in the molecules of that matter. This is because the energy from the infrared radiation can be absorbed by the molecules, leading to increased vibrational motion. The vibrations can involve the entire molecule, not just the electrons, which contributes to an increase in temperature and internal energy of the substance.

### Step 3: Analyzing the Relationship Between the Statements
Both statements are correct. Statement 1 accurately describes infrared waves as heat waves, and Statement 2 provides a valid explanation for why they are classified as such. The vibrations caused by infrared waves lead to an increase in temperature, which is the essence of heat.

### Conclusion
Both statements are true, and Statement 2 serves as a correct explanation for Statement 1. Therefore, the correct conclusion is that both statements are true, and Statement 2 explains Statement 1.

### Final Answer:
- **Statement 1 is true.**
- **Statement 2 is true and explains Statement 1.**

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