Balancing Nails
The challenge: stack 11 large nails on the head of a single nail. Oh yes you will be the
hit of the party with this one! Baffle your friends until you reveal the secret.
Materials
- 12 large nails (the bigger the better). Small ones don't work well
- Hammer
- Piece of wood
Watch Video
Process
1) Challenge a group of friends to stack 11 nails on the head of one without using
anything except the nails themselves. Let each one take a try until they get frustrated
and give up!
2) Take one nail and hammer it in a piece of wood about 1/2 inch. Make sure the top is
flat because we are going to set the other 11 on top of it.
3) Set one nail down on a flat surface to serve as the base.
4) Now start setting the nails on the one laying down with the nail heads close to the
first nail. Make sure each one is opposite of the previous one as the pictures to the right
illustrate.
5) Do this until you get to the end of the nail laying down.
6) Fit the last nail to lay down over the top of the others. The head of this nail should be
opposite of the head of the first nail you laid down as the base.
7) Pick the nails up using two fingers. Make sure each finger has hold of the base nail
and the nail tip at each end before lifting. Now gently lift up.
8) Watch as the nails heads lock together and form a secure structure.
9) Carefully set the nails to rest on top of the nail you hammered in previously. They will
balance if you set them in the middle where the center of gravity is located.
The Science:
Once the nails have been put together properly and locked into place (follow the
pictures to the right), we need to find the balancing point or center of gravity in order to
balance them onto the head of a single nail. Gravity pulls down on all of the
interconnected nails and can be focused on a single point called the center of gravity. If
we attempt to set the nails on any point other than the center of gravity, they would fall
down and not be supported. The center of gravity for our nail structure is the middle.
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