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# "So what should I do for the F.A.T. Chain Reaction?"

— Words of advice from Arthur Ganson

You can do ANYTHING in which the action of one 'object' or 'thing' triggers the action of another object' or 'thing'. The simplest things we are all familiar with - an arrangement of dominoes to topple in order, or a ball rolling down a track - are examples that use gravity and the fiendishly simple idea that a resting object can fall over!

Any object can be arranged to 'fall over' if it is balanced and then triggered, and every object will have its own unique characteristics. One domino falls very quickly, but a row of them will take more time, allowing viewers a chance to see what is happening. A ball on a track will take some time to 'fall', and this of course depends on the length and angle of the track.

Expanding on the use of gravity, many things can be set so that they 'fall' in a rather slow and controlled way:

• Any weight attached to a string that has been wound around a pole will fall, but it will have to unwind the string in the process. The weight will have to swing around the pole, and this can take considerable time. (The general idea here is that something that is 'twisted' will have to 'untwist', and in the process it will fall.)
• Something can inhibit the falling of a simple object by having to be moved out of the way - like air being forced out of a bag, or something that's really 'sticky'.
• Think about how to integrate objects and things that have energy stored in them, where the release of that energy will cause some kind of movement that can be 'used' to trigger something else. What can you do with a wind-up toy, a tape measure, a mouse-trap (be careful with your fingers!), or a music box?
• How could you use simple chemical reactions? Baking soda and vinegar gives off CO2 gas and will expand a balloon. The expanding balloon can be used to tip something over. What other simple and safe reactions can you think of using?
• Balloons are great for all kinds of things.....filled with helium they will 'fall' up - what could you do with that? Or how about popping the balloon? How can you make use of the instant change of size, or what can the popped balloon release?
• How about using water (just a little bit!) in different ways. Make it drain into something slowly to make it heavier and then unbalanced, or how about using water to soak soft paper like toilet paper to make it weaker, or how about making a bar of soap that is holding something up suddenly very slippery!

These are just a few ideas to get you started. It's possible to use virtually ANYTHING, as long as it somehow transfers the energy or movement. As you invent, think about a few things:

• How long will it take? Does it happen slow enough so that the audience can really see it and appreciate it?
• Is it visible from most directions? There will be audience all around.
• Is it repeatable? The first two hours are your chance to show off your creation to people as they walk around to look at things more closely. It's good to have things simple to set up again.
• Is it reliable? When we finally run the entire chain reaction, it's really exciting when things work! (of course, it's always the case that things won't work exactly as planned, so just do your best.)

No matter what happens, it's bound to be FUN!

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