OK, science teachers and physical science geeks, what's going on here?

"How to synchronize 5 metronomes" is really bugging me because I haven't a clue why it works. Can anyone help educate me and eliminate this bit o' frustration from my day? Thanks, I hope--!

It IS cool. videosift.com/video/How-to-synchronize-5... Asked by Pam_I_Am 41 months ago Similar questions: science teachers physical geeks Science.

Similar questions: science teachers physical geeks.

Tic toc The metronomes synchronise because the platform they are stood on is allowed to move. As the majority of the mass shifts one way, the board shifts the other (for every action there is an equal and opposite reaction). Any metronome not moving in the same direction as the majority .

Will have its swing momentarily shortened or lengthened until it gets into synch with the others. You can actually see it happening in the video. The center metronome keeps trying to move out of synch with the others, probably the weight is slightly out in comparison.

But the movement of the board keeps dragging it back in time.

Rolling platform The key is that the platform is placed on two soda cans that roll. Each metronome is a swinging pendulum. When it swings left, the table swings right to balance the forces.

On a stable table, it weighs so much more than the pendulum that it doesn't move a noticeable amount. But on the small rolling platform, there's a significant motion. Add a second out-of-synch metronome to the platform, and the jostling of the table will give the second metronome a kick in the direction that the other metronome wants it to go.

That is, the first metronome moves left, the table moves right. That yanks the fulcrum of the pendulum to the right, yanking the pendulum to the left, the direction the first metronome is going. At the start they'll fight each other, more or less randomly, but once they get into synch they'll stay in synch.

They reinforce each other. It would work with two metronomes, but it's more dramatic with five. Needless to say, it wouldn't work with digital metronomes, only pendulum ones.

Interestingly, it'll work even if the metronomes aren't set quite the same. They'll tend to center around the average of them. They can jostle the ones out of synch into behaving with the rest.

The page below has a good explanation and a closeup, so you can watch the platform roll. Sources: impactlab.com/2008/04/29/how-the-synchro... .

Look Look closely at the pop cans. The beating of the metronomes causes the platform to move back and forth. That transfers momentum from one metronome to another.

A metronome that is moving out of sync with the majority will get a little momentum added. Eventually they all get coerced into a common beat. This doesn't happen when they're all on the table..

It's all about Newton's 1'st law of motion. An object in motion tends to stay in motion unless acted upon by an outside force. Placing the metronomes on a board allows them to act as a single unit.

When the board holding the metronomes are placed on the cans it allows the collective inertia to move the board back and fourth. Initially all of the metronomes are out of sync causing an imbalance in the unit so there will be more inertia in one direction than the other. This inertia acts on the balance of the metronomes that are trying to push against the stronger force slowing them down slightly until such time as they all start swinging in sync, a state in which none of them are fighting against the greater inertia of the others in the system..

On the soda cans it each vibration from the metronomes pushes on the wood alittle and send it to the next metronome like a wave moving through water.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.