Potato Moving By Itself! Scientific explanation please?

[Meraki]

So last night we had baked potatoes. My dad noticed one of the potatoes rocking back and forth in the oven. He didn't think anything of it, and came back 20 minutes later and it was still going! Eventually it stopped, but started up again by itself a few minutes later, then stopped again. I did get a video, but I don't think I can upload it here.

The only explanation we could think of was the metal pan it was sitting on contracting in the heat of the oven. It gradually rocked more and more violently back and forth and then stopped. I am most definately not a scientist; it's very interesting, but I am far better at humanities! I was hoping some scientists could shed light on the mystery of the rocking potato!

[arc]

I'm not a scientist but I love a good mystery. I have seen this also, I believe it is more common than you might think. If the potato is positioned where it can slightly rock to one side from a very small amount of momentary force and then move back as the force is ended, an intermittent steam jet from from a puncture in the potato will provide the needed energy to cause the movement.

 

I'm sure you can recreate this phenomena with a little experimentation. You will need a potato with no holes or punctures to begin with. Start with several candidates and try finding a position that incurs a rock back movement when slightly pushed in the opposite direction. It must be a very balanced position needing little force to roll it against the gravity that will bring it back to its starting point. Once you find that perfect position make a puncture on the bottom of the potato to the side of that positions vertical center of balance, you want the puncture to be on the same side of center as that of the potato's start position. The puncture must face downward to the pan that it will be sitting on and as close to the pan as possible with the pan actually covering the puncture, this is critical.

 

As the potato is heated, steam builds inside until it escapes out through the puncture as a steam jet which pushes the potato over its center of balance momentarily. The potato then moves back as the internal pressure subsides, resetting the puncture onto the pan and creating a sufficient seal until the pressure once again reaches critical levels. This will continue as long as the potato has the moisture to produce adequate steam. Be careful and good luck.

[Endy0816]

I can't help but think that making a spud rocket would be totally awesome.

[arc]

I can't help but think that making a spud rocket would be totally awesome.

 

That would be used to put a spudnik satellite into orbit, right.

[fresh]

arc, try shrimp without a puncture. U will see a shrimp satellite !

[Meraki]

Oh, wow, I'd never thought of that! Thanks so much for the explanation! And yes, I shall try a few experiments! Shrimp satellites sound awesome!