Question

Which term best explains why you hear an echo?

1) diffraction
2) interference
3) refraction
4) reflection

Answer 1

The term that explains why you hear an echo is reflection, as sound waves from your voice hit a surface and are reflected back to you.

Step-by-step explanation:

The term that best explains why you hear an echo is reflection. When you shout "hello" and hear it a moment later, this is because the sound waves from your voice travel until they hit a surface and are reflected back to you. This is similar to how a ball bounces back to you when you throw it against a hard surface. The phenomena of diffraction, interference, and refraction involve waves bending around obstacles, combining with other waves, and changing direction as they enter different media, respectively, but these do not directly explain the occurrence of an echo.