Question

What should be the minimum distance between the listener and the reflector to hear an echo of sound propagating with a speed v ms-? (b) Does the speed of sound increase or decrease on a hotter day? Justify.

August 7, 2024

Answer

(a) Time = ${Distance \over Speed}$

or t = ${2d \over v}$

or d = ${v×𝑡 \over 2}$ = ${v×1 \over 2×10}$ (∵ Time = 0.1 s) = ${𝑣 \over 2d}$

(b) The speed of sound increases with temperature. So, on a hotter day speed of sound is more.

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