Can you get an egg into a milk bottle without breaking it?

Can you get an egg into a milk bottle without breaking it?

This experiment will amaze everyone!

Caution: make sure you ask a parent or guardian for help!

What you need:

  • Glass milk bottle or conical flask
  • Hard boiled egg
  • Small piece of newspaper
  • Lighter or matches

What to do:

Peel your hard boiled egg and make sure all the shell is removed.

Place the egg in the neck of the milk bottle, to check that the egg will sit neatly in the top of the milk bottle and that it won't slip through.

Remove the egg.

Ask your parent or guardian to light the piece of newspaper and carefully place it inside the milk bottle.

Quickly put the egg back on the neck of the bottle and watch what happens.

Did you see the egg get sucked into the bottle?

If you tip the bottle upside down the egg will remain inside: it is trapped.

Carefully remove any bits of paper from the top of the milk bottle and tip it up. Blow gently into the neck of the bottle and the egg should fall out. Amazing!

Check out this video to see the experiment in action:

Or watch on VideoJug

Why does it happen?

When the paper was lit, the air inside the bottle got hotter and expanded. The hot air had nowhere to go as the egg blocked the entrance to the milk bottle. When the flame went out, the air inside the bottle cooled down and contracted. This caused the pressure inside the bottle to decrease, making it lower than the air pressure outside the bottle. This higher pressure outside the bottle pushed the egg into the bottle.

When you blew into the milk bottle this increased the pressure inside the milk bottle so that it was greater than the air pressure outside the bottle. This pushes the egg out of the bottle. Very clever!