How does a Stethoscope Work?

Stethoscopes are used for listening to sounds from inside the body. When the shallow bell-shaped piece is placed against the skin, sounds are amplified through the rigid plastic diaphragm. The sounds then travel through the flexible tubing and the headset to tight-fitting earpieces, making the isolated sounds much easier to hear. Before the stethoscope was invented, doctors had to place their ears directly on a patient in an attempt to hear what was going on inside.