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प्रश्न
Explain why does the rear mirror of a motorbike start Vibrating Violently, at some particular speed of motorbike?
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उत्तर
When the frequency of the engine of motorbike corresponds with the natural frequency of the rear view mirror, die resonance takes place. Thus, the rearview mirror vibrates with a larger amplitude violently.
संबंधित प्रश्न
Give one example to illustrate forced vibrations.
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.
In following figure shows A, B , C and D represent test tube each of height 20 cm which are filled with water up to heights of 12 cm, 14 cm, 16cm and 18cm respectively. If a vibrating tuning fork is placed over the mouth if test tube D, a loud sound is heard.
- Describe the observations with the tubes A, B and C when the vibrating tuning fork is placed over the mouth of these tubes.
- Give the reason for your observation in each case.
- State the principle illustrated by the above experiment.
Two pendulums C and D are suspended from a wire as shown in the figure give below. Pendulum C is made to oscullate by displaying it from its mean position. It is seen that D also starts oscillating.
(i) Name the type of oscillation, C will execute.
(ii) Name the type of oscillation, D will execute.
(iii) If the length of D is made equal to C then what difference will you notice in the oscillations of D ?
(iv) What is the name of the phenomenon when the length of D is made equal to C ?
The diagram below shows three different modes of vibration P, Q and R of the same string of a given length.
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 |
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| P | Q | R |
- Which vibration will produce a louder sound and why?
- Which vibration will produce sound of maximum shrillness (or pitch) and why?
- What is the ratio of wavelength of vibrations P and R?
State two ways in which resonance differs from forced vibrations.
Explain a tuning fork (vibrating) is held close to ear. One hears a faint sound. The same vibrating tuning fork is placed on table, such that its handle is in contact with table, one hears a loud sound.
Explain free and forced vibrations. Give an experimental arrangement to illustrate the phenomenon of resonance.
When the stem of vibrating tuning fork is pressed on a table, the tabletop starts vibrating. These vibrations are definitely an example of ______.
