Flash Education

Question

Figure shows the position of layers of air, at one moment, as a sound wave of constant frequency passes through the air. Compressions are labelled C. Rarefactions are labelled R.
(a) State how figure would change if (i) the sound had a higher frequency, (ii) the sound were louder. (b) On figure, draw a line marked with arrows at each end to show the wavelength of the sound.

Sound CBSE Class 9

CBSE, Class 9, Exam Idea, Science

August 7, 2024

Answer

(a) (i) More compressions and rarefactions will be produced in a given time interval (i.e., C and R will become closer together).

(ii) At compressions, layers become closer together. At rarefactions, layers become farther apart (i.e., C will narrower and rarefactions wider).

(b) Distance between two compressions or two rarefactions are called wavelength (⋌).

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