Air tricks and experiments - section 2

Does air weigh anything

All you need:
3-foot length of wood (as a yardstick)
a cord or wire
a chair back or a rod
a large balloon
a small can or box

Step 1: Drill holes (or make notches) from each end of a length of wood, as it's shown on the picture bellow.
Then, make a hole in the exact center of the stick, 18 inches from each end.

Step 2: Place a cord or wire through the center hole and suspend the stick from a chair back or a rod.

Step 3: Blow up a large balloon (you can use a beach ball instead of the baloon as well).

Step 4: Tie its mouth tight and hang it from one of the end holes of the stick.

Step 5: Suspend a small can from the other hole.

Step 6: Put a little sand or rice in the can until the stick balances. Let the air out of the balloon.

What you will see: The can sinks down as the air is let out of the balloon.

Why: When the air leaves the balloon, the balloon becomes lighter. Air has weight. At sea level, air weighs 1 and 1/4 ounces per cubic foot.

On a mountaintop, air is a little thinner and weighs less.

Does air weigh anything