Best Ever Q&A Space Our World Nature History Science & Technology Human Body Senses & Organs Science of Life Chemicals & Matter Atoms & Molecules Materials Forces & Energy Sound Electricity & Magnetism Heat & Light Everyday Science Industry Transportation Computers Machines Ships Undersea Exploration Land Travel Cars Flight Structures Buildings Farming	Sound How does sound travel down telephone wires? Why does the sound of a racing car engine change as it drives past us? How is loudness measured? How fast does sound travel? How do we hear sounds? What is sound?   Previous: Back to Sound Book: Best Ever Q&A Section: Science & Technology Chapter: Sound