Advertisements
Advertisements
प्रश्न
The rearview mirror of a motorbike starts vibrating violently at some particular speed of the motorbike, what could be done to stop the violent vibrations.
Advertisements
उत्तर १
This can be stopped by mounting the engine on such a structure, say steel springs that absorb the vibrations of the engine without communicating them to the frame and in this condition, the rearview mirror attached to the frame will not vibrate violently.
उत्तर २
(i) The frame of a motorcycle along with the rearview mirror is found to vibrate violently when it is driven to a particular speed. This happens when the frame has the natural frequency of vibration equal to that of the piston when the engine is driven at that particular speed.
(ii) This phenomenon is called ‘resonance’. In this phenomenon when a body begins with the natural frequency of the others vibrating body B, then A begins to vibrate violently with the maximum amplitude.
(iii) This can be stopped by mounting the engine on such a structure, say steel springs that absorb the vibrations of the engine without communicating them to the frame and in this condition, the rearview mirror attached to the frame will not vibrate violently.
संबंधित प्रश्न
Describe a simple experiment to illustrate the phenomenon of resonance and explain it.
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.
When a troop crosses a suspension bridge, the soldiers are asked to break steps. Explain the reason.
Why are the stringed instruments like guitar provided with a hollow sound box?
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 ?
In fig. shows two tuning forks P and Q of the same frequency mounted on separate sound boxes with their open ends facing each other. The fork A is set into vibration. (i) Describe your observation. (ii) State the principle illustrated by this experiment.
When acoustic resonance takes place, a loud sound is heard. Why does this happen? Explain.
Explain a person walking past a railway line, in the middle of night hears a ringing sound along with the sound of his footsteps.
What do you understand by free (or natural) vibrations?
What do you understand by free vibrations of a body? Draw a displacement-time graph to represent them. Given one example.
