Labels:text | screenshot | font OCR: For simplicity, our simulation shows sound waves travelling at a steady speed. In an actual situation, small differences in air pressure and temperature along the wave path would vary the wave speed. We may not hear an echo if the original sound is too weak for enough of the wave to reach a reflecting object or if the reflecting object is too small to bounce back enough of the wave. Also, we may not hear an echo if the sound waves are absorbed by objects in our surroundings or if we are too close to the reflecting object.
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