Right now, every sound you hear is actually air being repeatedly squeezed and stretched. When someone speaks, their vocal cords vibrate, pushing air molecules together (compressions) and apart (rarefactions). This ripple of pressure differences travels outward at 330 m/s and enters your ear canal, vibrating your eardrum — and your brain interprets that vibration as sound. Bats navigate by sending out ultrasound pulses and listening for the echoes bouncing back from insects and walls. Doctors use the same principle with ultrasound scanners to see inside your body without any surgery!
This introduction covers Invisible Pressure Waves Around You within Sound Waves for GCSE Physics. Revise Sound Waves in Waves for GCSE Physics with 16 exam-style questions and 15 flashcards. Use this page as part of a wider topic revision path rather than treating it as an isolated fact. It is section 1 of 13 in this topic. Use this introduction to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Sound Waves
What type of wave is sound?
Describe how a sound wave is produced and how energy is transferred by a longitudinal wave.
Quick recall flashcards
Sound wave type?
Longitudinal
What is an echo?
Reflection of sound waves from a surface