Safety: This stethoscope has a funnel on both ends to prevent the small tube being stuck into the ear. Never push small objects like pencils or tubes into your ear canal.
What to do
Place the funnels in either end of the plastic tubing. If this is difficult, soak the ends of the tubing in warm water. This will soften the plastic and allow you to place the funnel into the tube ends more easily.
There you go, now you have a handmade stethoscope!
Place one end of the stethoscope directly over your heart and the other end at your ear to hear your heart beat.
Try listening to other parts of your body.
What's happening?
Sound is made up of vibrations. When anything makes a sound, it 'vibrates', just like the word buzzzz vibrates in your throat. These vibrations make the air around them vibrate, and then these vibrations spread through the air to reach your ears.
Sound can also travel through liquids and solids, just about anything really, except for nothing (if you can find it). One place where you would find nothing is in the vacuum of space, where you will truly find no air; nothing at all for sound to travel through. Sound in space would go nowhere - if you tried to talk in space, your words would stop at your lips!
Back to the stethoscope. When your heart beats, the vibration of this movement travels through your chest and hits the funnel in your home-made stethoscope. The sound then travels through the tubing and the air in the tubing to reach the funnel next to your ear.
Your heart beat is then amplified by the funnel at your ear. When sound is amplified, or made louder, the amount of air the sound makes vibrate becomes bigger. In this case, all the air in the funnel starts to vibrate, making the beats louder. The sound then reaches your ear and you can listen to all sorts of interesting sounds in your body.
Applications
Stethoscopes are used to hear sounds in the body. They are used to listen to the heart, lungs and intestinal tract. They are also used when measuring blood pressure.
Throughout an average lifetime, the heart beats more than two billion times, pumping enough blood to fill over 100 full-sized swimming pools. Despite this amazing workload, the heart never stops to rest.
If you hold your hand in a fist, you will get an idea of the size of your heart. It automatically contracts about once a second and pumps blood around your body. The heart is actually two pumps side by side, separated by a muscular wall. One pump sends blood to your lungs to absorb oxygen and the other pump sends blood all around your body.
You have a pulse because when blood flows out of your heart, a wave of high pressure passes through your arteries causing them to expand slightly, and then return to their normal size. This momentary change is what you feel as a pulse.
Your heart rate is your heart's rhythm. Your heart does not always beat at the same rhythm as it all depends on how much oxygen your body needs. This is why your heart rate gets faster when you exercise.
You will need two small kitchen funnels and around 50 cm of plastic tubing.
Place the funnels in either end of the plastic tubing. Now you have a handmade stethoscope!
Stethoscopes are used to hear sounds in the body. They are used to listen to the heart, lungs and intestinal tract. They are also used when measuring blood pressure.
The Lloyd’s Register Educational Trust funds education, training and research programs in transportation, science, engineering, technology and the safety of life, worldwide for the benefit of all.
bankmecu is a 100% customer owned bank who believes in the education of young people and the importance of science in understanding our community and environment. bankmecu is the proud founding partner of Science by Email.
