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Assertion: soldiers are asked to break s...

Assertion: soldiers are asked to break steps while crossing the bridge.
Reason: The frequency of marching may be equal to the natural frequency of bridge and may lead to resonance which can break the bridge.

A

If both A and R are true and R is the correct explanation of A.

B

If both A and R are true but R is not the correct explanation of A.

C

If A is true but R is false

D

If A is false but R is true.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that soldiers are asked to break their steps while crossing a bridge. This is a common practice in military drills when crossing bridges. 2. **Understanding the Reason**: - The reason provided explains that the frequency of the soldiers' marching can match the natural frequency of the bridge. This is significant because when two frequencies match, resonance occurs. 3. **Concept of Resonance**: - Resonance is a phenomenon that occurs when an external force is applied at a frequency that matches the natural frequency of a system. In this case, if the soldiers march in step, their marching frequency can resonate with the bridge's natural frequency. 4. **Effects of Resonance**: - When resonance occurs, the amplitude of oscillation of the bridge can increase significantly. This can lead to excessive vibrations, which may cause structural damage to the bridge. 5. **Conclusion**: - The assertion is true because soldiers are indeed instructed to break their steps to avoid resonance. The reason is also true as it correctly explains the phenomenon of resonance and its potential effects on the bridge. Therefore, both the assertion and the reason are correct, and the reason provides a valid explanation for the assertion. ### Final Answer: Both the assertion and the reason are true, and the reason is the correct explanation of the assertion. ---
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