Emma Carlson Berne 
Loud! [PDF ebook] 

The rumble of thunder is a sign of a storm, and by listening we can estimate how far away that storm is. Readers explore the principles of sound energy, including qualities of sound, sound waves, and the speed of sound. Readers will also learn how our ears hear sounds, and why some sounds are out of the range of human hearing. Sidebars explain sonic booms and measures of sound, while photographs depict sources of sound energy in our world.