A physician’s stethoscope is a sound-capturing device. Its sound gathering end is formed by a flat drumhead. Sounds detected by this surface are transferred through the hose to the broadcasting end of the tool. There, vibrations leave the tube and are detected by the physician’s ear.
Things Required:
Two funnels
1-foot-long plastic tubing
Directions:
Slip each end of the plastic tubing over the spout end of a funnel. To test your device, place one of the funnels against the wall. The rim of the funnel opening should lie flat on the surface of the wall. Place the opening of the other funnel around your ear. Gently, tap on the wall. What do you hear?
Now, place one of the funnels over your heart. Make sure the rim lies flat against your skin. Move the other funnel to your ear. What do you hear?
Keep listening. Take a deep breath. Can you hear the air as it travels along the passageways of your lungs?
This Is What Happens:
Your heart is a powerful muscle. As this muscle contracts, it pumps blood through the vessels of your body. To ensure that the pumped blood follows a one-way route, valves shut off and block the return flow of blood. The closure of these valves within the heart produce the sound what we call a heartbeat. As this vibration travels through the body, it spreads out. The large collector of the stethoscope detects and concentrates these sounds. At the ear, the vibrations are detected as sound.
