Question 15 — Two identical sound sources are - Questions at the end of the chapter - Chapter 10 - Sound Waves: Characteristics and Application (Exploration

Last updated at July 3, 2026 by

Question 15
Two identical sound sources are placed at A and B — one in air and one submerged in water (Fig. 10.34). Both produce sounds at the same time, which travel horizontally to the vertical side of the cliff and come back. If the time taken by the sound to return to A is 4.5 times than that of B, what is the ratio between the speeds of sound in air and water?
View Answer Hide Answer
  • Same distance, so time is inversely proportional to speed: \(\dfrac{t_A}{t_B}=\dfrac{v_B}{v_A}=4.5\).
  • Hence \(\dfrac{v_{\text{air}}}{v_{\text{water}}}=\dfrac{v_A}{v_B}=\dfrac{1}{4.5}\approx \mathbf{1:4.5}\) (sound is faster in water).
Ratio of Speeds Same distance, so time is inverse of speed t_A / t_B = v_B / v_A = 4.5 v_air to v_water is about 1 to 4.5
Back to: 10.6.3 Speed of Sound
Remove Ads Share on WhatsApp
CA Maninder Singh's photo - Co-founder, Teachoo

Made by

CA Maninder Singh

CA Maninder Singh is a Chartered Accountant with 16+ years of practical experience and 20+ years of teaching experience. At Teachoo, he simplifies Accounts, Tax and GST with step-by-step examples so students can apply concepts confidently in exams and real life.

For an uninterrupted learning experience, students can use Teachoo Black to remove ads and focus better.