Echoes and How Sound Travels: Echo Valley

Hello… hello… hello! In Echo Valley, a tall rocky cliff sends your voice back to you. Zoe and Mia are talking on a cup telephone, frogs croak on the pond and, as the Sun goes down, little bats come out.

Remember: Sound travels through gases (like air), liquids (like water) and solids (like wood or string). It travels faster through water than through air. In space there is no air, so sound can’t travel there at all. An echo is sound bouncing off a hard surface, like a cliff or a wall. Soft things like curtains and cushions soak up sound, so they make fewer echoes. Bats use echoes to find their food in the dark.

Magic trick: Light and sound both bounce: light bouncing is a reflection, sound bouncing is an echo.