Advertisements
Advertisements
प्रश्न
Explain free and forced vibrations. Give an experimental arrangement to illustrate the phenomenon of resonance.
Advertisements
उत्तर
When a system or a body vibrates without receiving impulses from another system or body, its vibrations are said to be free vibrations. However, when a system or body vibrates on account of impulses received from another system or body, the vibrations are called forced vibrations. In such a case the body or the system vibrates with the frequency of the impulses received and not with its natural frequency.
Experiment Arrangement to illustrate Resonance: In the figure, the two pendulums have exactly equal lengths. However, the bob of the pendulum A is heavier. Displace the bob of the pendulum A by a little distance in a direction perpendicular to the plane containing the two pendulums. Then release the bob. The pendulum A will begin to oscillate. After a short while, you will find that the pendulum B also begins to vibrate. Note that the two pendulums have the same frequency. The pendulum A through the rubber tube applies impulses of the same frequency on the pendulum B Hence, the pendulum B begins to vibrate.
संबंधित प्रश्न
Distinguish between the free (or natural) and forced vibrations.
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.
How do you tune your radio set to a particular station ? Name the phenomenon involved in doing so and define it.
Name the phenomenon involved in tuning your radio set to a particular station and define it.
Which characteristic of sound makes it possible to recognize a person by his voice without seeing him?
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).
Differentiate between the following:
Free and forced vibrations.
Explain why stringed musical instruments, like the guitar, are provided with a hollow box.
What do you understand by forced vibrations?
