Floating Ball

What you need:

1. A small light ball (like a ping pong ball) covered with foil

2. A circular piece of paper

3. A straw

4. Some tape

How to do:

1. Cut a slit on the circular piece of paper to the center.

2. Roll it into a funnel shape and tape it inside and outside.

3. Cut a small slit just enough to let the short end of the straw to pass through.

4. Insert the short end of the straw through the hole (not completely but just enough to stick it to the funnel) and tape it to the funnel.

5. Place the ball inside the funnel and blow through the other end of the straw. You would see the ball floating.

Why it happens:

When you blow air through the straw into the funnel, it gives the required force to counter the effect of gravity on the ball. This makes the ball appear to float.