Top 10 Most Curious States of Equilibrium.

These simple experiments you can try at home. They are described in a book "La Science Amusante" by Tom Tit (pen name of Arthur Good) with illustrations by Poyet, published in Paris in 1890. (translated from Russian version by Avi Abrams)

1. Pencil + pocket knife

Simply stick the pocket knife's blade into a pencil and balance it on its tip. (depending on how wide you open the knife, the pencil will tilt accordingly)

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2. Soup ladle + pocket knife

Try to fill the spoon with sugar, increasing its weight: the whole structure will still stand, with knife rising higher till the new state of balance is achieved.

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3. Overturned Plate + soup ladle + spatula

Even more interesting is the stable equilibrium of overturned plate, balancing on the bottle's edge.

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4. Egg + bottle

Stick a couple of identical forks into a cork (make a small indent in this cork to make a better fit with an egg's surface) Then you can easily balance the egg - on the edge of a bottle!

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5. Two forks + a quarter

It's possible to pour water, with a coin balancing on the rim of a pouring glass (with two forks attached to the coin). Ask your friend to try it, and he'll probably refuse, but it's really not that difficult.

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6. Balancing a plate on a needle

Most of the time the object has to rotate in order to achieve such balance, but in this case the plate is STANDING STILL.
Slice a couple of corks in half, and place them as shown on the plate's edge, with forks hanging slightly on the angle. Place the plate on a tip of a needle. Voila! You can even rotate this system, and it should rotate steadily for long time.

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7. Amazing Equilibrium of Pens and Pencils

This is a bit more complex structure, but even more fascinating.
Hang a pencil with a thread attached to its tip (and 2 balancing knifes), add another pencil, balanced with 2 sharp-tipped pens.

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8. Lift 15 matches with one

First place 14 matches on top of one match, laying perpendicular to the rest (as shown). Then you can lift all of these matches from the table, if you put one more match on top of crisscrossed ones.

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9. Balance all 28 domino pieces on one!

Exactly as shown. Start building with three pieces for support. Then remove the other two supporting pieces from the sides - the structure will balance on one domino piece (just don't move the table)

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10. Candle Wax Motor

This engine will work without any steam, gas or electricity. All you need is a ... candle.
First, balance the candle (pierced with a pin) between two glasses.
Then light the candle from BOTH ends.
As the wax melts, it will drip into a cup, making corresponding end of a candle lighter - so the other end will swing lower, causing the wax to drip from this other end faster, making this end lighter... etc.

The candle's oscillations will soon increase, and you will observe A WAX MOTOR in action.
You can even carve out little people figures, attach them to both ends, and watch them ceaselessly work.

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More examples:

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