What you need:
- a small table
- a tablecloth (or similar piece of material) with no hem
- various heavy items (preferably unbreakable ones) eg metal cutlery, cups, salt shaker, fruit bowl etc
- nerves of steel
What to do:
- Spread the cloth on the table and smooth it out.
- Set the table with the items you have selected.
- Pull the tablecloth off the table with a quick jerk. Be sure to not lift the tablecloth upwards as you pull on it.
- Take a bow.
How far do the items move? Why do they stay on the table? Or try putting a coaster on a glass, with a coin on the coaster – flick the coaster out sideways for the coin to fall into the glass.
Be sure to practise this trick many times beforehand, using unbreakable items at least until you are confident of being able to make it work every time.
Objects have mass (weight) and inertia, or a tendency to stay still if they are still, or keep moving if they are in motion. When the tablecloth is whipped out from under the items there isn’t enough time for them to start moving sideways, and so they mostly stay where they are, falling 1mm or so onto the table top as the tablecloth comes out from underneath them.