Why do soldiers march disorderly while crossing a bridge?...
Why do soldiers march disorderly while crossing a bridge?
To prevent resonance on the bridge
To set the bridge into resonance
To make the b ridge collapse
To spread their weight evenly on the bridge
Correct answer is A
Soldiers march disorderly while crossing a bridge to prevent resonance because when soldiers march in orderly manner across a bridge, they generate a rhythmic oscillation of wave on the bridge and at a certain point, would start oscillation to the same rhythm as that of the marching steps. This oscillation would reach a maximum peak when the bridge can no longer sustain its own strength and hence collapses. So for this reasons, soldier are ordered to march disorderly while crossing a bridge.
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