Advertisements
Advertisements
Question
The frequency of the stretched string of a fixed length is f when it is plucked in the middle. Where should it be plucked so that string vibrates with frequency (i) 2f, (ii) 3f?
Draw diagrams to show these vibrations and name them.
Advertisements
Solution
(i) The stretched string should be plucked at one-fourth part of the string to obtain frequency 2f:
(ii) The string should be plucked at one-sixth part of the string to obtain frequency 3f.
These vibrations are shown in the figure and are named as a fundamental, first overtone, and the second overtone respectively.

RELATED QUESTIONS
The ratio of the amplitudes of two waves is 3 : 4. What is the ratio of their loudness?
A person is standing at the seashore. An observer on the ship which is anchored in between a vertical cliff and the person on the shore fires a gun. The person on the shore hears two sounds, 2 seconds and 3 seconds after seeing the smoke of the fired gun. If the speed of sound in the air is 320 ms-1 then calculate:
1) the distance between the observer on the ship and the person on the shore.
2) the distance between the cliff and the observer on the ship.

The quality of a sound depends on the amplitude of wave.
The time period of a wave is 2 s. Its frequency is ..........
If the amplitude of a wave is doubled, what will be the effect on its loudness?
Two waves of the same pitch have amplitudes in the ratio 1:3. What will be the ratio of loudness?
Explain the following and illustrate your answer by drawing appropriate diagram:
Pitch
The same musical note when played on a piano and when played on a flute sounds different.
Name one main factor on which each character such as intensity, pitch, and quality of musical sound depends.
A 0.6 m long stretched wire is made to vibrate in two different modes as shown in figure
(a)

(b)

(i) If the frequency of the note produced in (b) is n, what is the frequency in case (a)?
(ii) In which case (a) or (b), is the note louder? Give reasons.
(iii) In which case is the pitch higher? Give reason.
