Advertisements
Advertisements
प्रश्न
Explain a person walking past a railway line, in the middle of night hears a ringing sound along with the sound of his footsteps.
Advertisements
उत्तर
When the vibrations produced by the feet of the person are impressed on the rails, they vibrate with forced vibrations, thereby producing a loud sound.
संबंधित प्रश्न
Give one example to illustrate forced vibrations.
Resonance is a special case of ______ vibrations, when frequency of the driving force is ______ natural frequency of the body.
Why is a loud sound heard at resonance?
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.
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.
Explain why are soldiers asked to walk out of step while crossing bridges?
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.
A string stretched between its ends is made to vibrate by placing the stem of a vibrating tuning fork at its one end. State three ways how you will increase the frequency of note produced by the string.
What do you understand by free (or natural) vibrations?
What are the factors that affect the frequency of a vibrating string and how do they affect the frequency?
