# Homework Help: Domino experiment

1. Sep 9, 2006

### cerebro

I made such experiment: I calculated the time dependence on the number of dominoes. The dominoes are set up in a row with a constant distance between them.

However the measurements are not necessarily exact and that is why I have a question:

What should be the relation between the number of dominoes set up in a row and the time that takes them to be demolished after I push the first one.

2. Sep 10, 2006

### Delzac

hmmm......i got a feeling that rotational inertia also needs to be taken into account, since the domino is rotating(sort of).

3. May 2, 2007

### Toyman991

A similar question has stymied me for quite some time; that being, for a given domino shape/size/weight, is there an optimal spacing that will produce the fastest wave propagation?

4. May 3, 2007

### SEG9585

I would think it's a little predictable to some extent, since the only forces on a domino are its inital impulse plus gravity. When dominos are spaced farther apart, they hit the next domino with a greater linear impulse but transmit a smaller angular momentum (because it hits the domino at a point closer to the center of mass -- less r). On the other hand, closer dominos transmit more angular momentum per linear impulse, but the impulse is less because it has had less time to accelerate. Interesting question, and I bet there is a "best-case" solution for a standard size/weight domino that would take a few iterations to solve. When I have a little time to think about it more I'll respond again...