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Featured Articles :: The Science Corner

by Mad Science N.E. Central Florida (Mad Science of NE Central Florida)

Test Your Lung Capacity
Learn more about your lungs with this cool experiment.

We need air to do all the fun things that we like to do! How do we use it? We breathe it! So how large do you think your lungs are; the size of a sandwich bag or the size of a drink box? This experiment will help you see how just how big your lungs really are!

Materials:
• Empty 2-liter plastic soda bottle
• 5 galloon bucket
• Plastic tubing
• Water
• Permanent marker
• A parent, friend, brother or sister to help and also measure against!

Procedure:
Step 1: Fill the bucket with water.
Step 2: Take the 2-liter bottle and push it down into the bucket to fill it up to the top with water.
Step 3: Hold your hand over the top of the 2-liter bottle you just filled with water. Turn it upside down, so the opening is facing the floor, and place it back in the bucket of water.
Step 4: Ask an adult or friend to hold the 2-liter bottle upside down in the bucket. Make sure no water comes out! If it does, go back to step 2.
Step 5: Place one end of the plastic tubing down into the bucket of water and up into the mouth of the 2-liter bottle.
Step 6: Take a deep breath and blow into the other end of the plastic tubing. Keep blowing until you cannot breathe any more!
Step 7: When you are done, carefully lift the 2-liter bottle out of the water (careful not to tilt it to the side!) and use the permanent marker to mark the point where the air and water meet inside.
Step 8: If you wish, return to step 2, and have your friend, parent, or brother or sister try the experiment next!
Step 9: Take few minutes to explain the science behind the experiment to your parents!

The Science Behind It!
Every day, humans continuously breathe in and out, carrying air to and from our lungs. The amount of air we take into the lungs in an average breath is called our lungs’ Tidal Volume. However, our lungs can hold 8 to 12 times as much as we breathe in during a normal breath! In this experiment, you measured the maximum amount of air that you can breathe out after taking your deepest possible breath. This amount is known as your lungs’ Vital Capacity. The mark you drew on your soda bottle shows the limit of your lungs’ Vital Capacity.
Our vital capacity depends on a lot of things, like our age, weight, sex, and physical fitness. For example, females tend to have a lower capacity than males. Heavy smokers have a much lower capacity than nonsmokers, and top athletes have a much bigger capacity than most. Exercising helps increase our lungs’ vital capacity, bad habits like smoking or inactivity helps reduce it!

Mad Science sparks the imagination and curiosity of children everywhere by providing fun, interactive and educational activities. Please visit our website at www.madscience.org/necentralfl for more information on our programs!