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प्रश्न
Explain why are soldiers asked to walk out of step while crossing bridges?
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उत्तर
When the soldiers walk in step, they produce some fixed frequency. If this frequency corresponds to the natural frequency of the bridge, the resonance can take place. This, in turn, will make the bridge to vibrate violently, and hence make it collapse. To avoid such a situation, the soldiers are asked not to march in step.
संबंधित प्रश्न
The diagram above shows a wire stretched over a sonometer. Stems of two vibrating tuning forks A and Bare touched to the wooden box of the sonometer. It is observed that the paper rider (a small piece of paper folded at the centre) present on the wire flies off when the stem of vibrating tuning fork B is touched to the wooden box but the paper just vibrates when the stem of vibrating tuning fork A is touched to the wooden box.
1) Name the phenomenon when the paper rider just vibrates.
2) Name the phenomenon when the paper rider flies off.
3) Why does the paper rider fly off when the stem of tuning fork B is touched to the box?
How does the medium affect the amplitude of free/natural vibrations of a body?
Why is a loud sound heard at resonance?
In following figure shows A, B, C and D are four pendulums suspended from the same elastic string XY. Lengths of pendulum A and D are equal, while the length of pendulum B is smaller and the pendulum C is longer. The pendulum A is set into vibration.
(a) what is your observation? (b) Give reason for your observation.
Differentiate between the following:
Free and forced vibrations.
Explain Why are stringed musical instruments provided with large sound boxes?
What are the factors that affect the frequency of a vibrating string and how do they affect the frequency?
