Question

Why are soldiers in a troop asked to break steps on a suspension bridge?

Answer 1

1. When troops start marching “in step”, then they produce periodic force.
2. Troops are stopped marching on the bridge in step because if the frequency of periodic force matches with the natural frequency of vibration of the bridge that causes resonance and the bridge being to vibrate with large amplitude.
3. It may cause a failure of the bridge.