Stethoscopes: Drum to Drum | God's World News
Stethoscopes: Drum to Drum
Take Apart SMART!
Posted: December 20, 2019

Stethoscopes have been around for a long time—and the idea that makes them work has been around since creation.

You could think of a stethoscope as two drums connected by a tube. One drum creates sound waves. One feels sound waves. The first drum is the chestpiece of the stethoscope. The second drum is your eardrum. Both drums have a thin diaphragm, like the head of a drum. Anything that moves the stethoscope’s “drumhead” causes that diaphragm to vibrate. This vibration pushes air molecules into waves. These pressure waves move outward like ripples when you throw a rock into a pond. But unlike pond ripples, these sound waves can’t keep spreading wider and wider until they disappear. They are trapped inside a stethoscope. In fact, the waves are magnified as they are forced through the stethoscope’s narrow tubes.

The sound waves finish their journey as they escape out the holes of earpieces. The waves travel down your ear canal and reach your eardrum. Sound waves banging into your eardrum’s diaphragm cause it to vibrate. Tiny bones touching the other side of your eardrum feel the vibration of your eardrum. There are nerve endings attached to those little bones. Nerves send the vibration information to your brain. You brain interprets the vibrations as sound. Isn’t it incredible that God created our brains to be able to figure out which sounds are your dad’s snoring, the cat meowing, your sister playing violin, or your brother practicing Spanish?