Vibrational kinetic energy is insignificant at low temperatures.
Interatomic forces are responsible for vibrational kinetic energy.

Options

A. If both Assertion and Reason are true and the reason is correct explanation of the Assertion.
B. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
C. If Assertion is true, but the Reason is false.
D. If Assertion is false but the Reason is true.

Answer

To analyze the given statements about vibrational kinetic energy and interatomic forces, we can break down the solution into clear steps:

### Step 1: Understand the Assertion
The assertion states that "vibrational kinetic energy is insignificant at low temperatures." This means that at low temperatures, the energy associated with the vibrational motion of molecules is minimal.

### Step 2: Explain Why the Assertion is True
At low temperatures, the thermal energy available to the molecules is not sufficient to excite them to vibrate significantly. The vibrational motion of molecules requires a certain amount of energy to overcome the interatomic forces that hold them in place. Since this energy is not available at low temperatures, the vibrational kinetic energy is negligible.

### Step 3: Understand the Reasoning
The reasoning states that "interatomic forces are responsible for vibrational kinetic energy." This implies that the forces between atoms or molecules play a crucial role in the vibrational motion.

### Step 4: Explain Why the Reasoning is True
Interatomic forces, such as Van der Waals forces or covalent bonds, create a potential energy landscape for the molecules. When the temperature increases, these forces can be overcome, allowing the molecules to vibrate more freely. This increased vibrational motion translates into vibrational kinetic energy.

### Step 5: Analyze the Relationship Between Assertion and Reasoning
While both the assertion and the reasoning are true, the reasoning does not directly explain the assertion. The assertion focuses on the effect of temperature on vibrational kinetic energy, while the reasoning discusses the role of interatomic forces in enabling vibrational motion. Therefore, they are related but not causally linked.

### Step 6: Conclusion
Based on the analysis, both the assertion and the reasoning are true, but the reasoning does not adequately explain the assertion. Thus, the correct answer is that both statements are true, but the reasoning does not support the assertion.

### Final Answer
Both assertion and reasoning are true, but the reasoning does not explain the assertion.

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