how does sound get generated when you whistle? I.e. what creates the sound/vibrations when you whistle on your lips?
While I whistle, there is a whole lot of action taking place. My lips vibrate ever so lightly, along with the air around my lips and inside my mouth, this in turn causes the air molecules in front of me to vibrate - meaning it compresses and expands. This causes a sound wave, (Sound waves consist of areas of high and low pressure) and the closer together these compressions and expansions the higher the note will be. I can lower the pitch by increasing the size of cavity in my mouth (by lowering my jaw) and increase the pitch by reducing the size of cavity in your mouth.