Question

Echoes are due to; 1) Refraction of sound waves; 2) Polarisation of sound waves; 3) Diffraction of sound waves; 4) Reflection of sound waves

Answer 1

I guess it is reflection of sound waves

Answer 2

$\huge\mathcal{Answer:}$

Like any wave, a sound wave doesn't just s

when it reaches the end of the medium or when it encounters an obstacle in its path. Rather, a sound wave will undergo certain behaviors when it encounters the end of the medium or an obstacle. Possible behaviors include reflection off the obstacle, diffraction around the obstacle, and transmission