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प्रश्न
When a troop crosses a suspension bridge, the soldiers are asked to break steps. Explain the reason.
When a troop crosses a suspension bridge, the soldiers are asked to break their steps. Why?
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उत्तर
When a troop crosses a suspension bridge, the soldiers are asked to break steps. The reason is that when soldiers march in steps, all the separate periodic forces exerted by them are in same phase and therefore forced vibrations of a particular frequency are produced in the bridge. Now, if the natural frequency of the bridge happens to be equal to the frequency of the steps, the bridge will vibrate with large amplitude due to resonance and suspension bridge could crumble.
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संबंधित प्रश्न
In the diagram below, A, B, C, D are four pendulums suspended from the same elastic string PQ. The length of A and C are equal to each other while the length of pendulum B is smaller than that of D. Pendulum A is set into a mode of vibrations
1) Name the type of vibrations taking place in pendulums B and D?
2) What is the state of pendulum C?
3) State the reason for the type of vibrations in pendulum B and C.
What are mechanical waves?
Resonance is a special case of ______ vibrations, when frequency of the driving force is ______ natural frequency of the body.
When a body vibrates under a periodic force, the vibrations of the body are ______.
In Fig. A, B, C and D are four pendulums suspended from the same elastic string XY. The lengths of pendulum A and D are equal, while the length of pendulum B is shorter and of the pendulum C is longer. Pendulum A is set into vibrations.
- What is your observation about the vibrations of pendulum D?
- Give reason for your observation in part (a).
- What type of vibrations take place in pendulums Band C?
- Give reason for the answer in part (c).
What do you mean by resonance? When does resonance occur?
Explain why are soldiers asked to walk out of step while crossing bridges?
Explain Why are stringed musical instruments provided with large sound boxes?
Describe a simple experiment to illustrate the phenomenon of resonance and explain it.
