How does the methyl alcohol cork demo with alligator clips work?

[katie14618]

I was at a science museum earlier and I saw a demonstration where methyl alcohol was put in a bottle that had two nails sticking out of the sides. Alligator clips were connected to the nails and something was connected to the clips (I think they said it was a grill starter). There was a cork in the bottle. When the thing connected to the alligator clips was pressed the cork was blown off of the bottle.

I don’t know what it was supposed to be a model of but I think it was either an engine or a piston (I missed the beginning of the demonstration).

I would like to build one of theses for a project for my AP physics class but I need more detailed directions on how to make it. I mainly need to know what it was that was connected to the alligator clips.

 

[OlderDan]

I was at a science museum earlier and I saw a demonstration where methyl alcohol was put in a bottle that had two nails sticking out of the sides. Alligator clips were connected to the nails and something was connected to the clips (I think they said it was a grill starter). There was a cork in the bottle. When the thing connected to the alligator clips was pressed the cork was blown off of the bottle.

I don’t know what it was supposed to be a model of but I think it was either an engine or a piston (I missed the beginning of the demonstration).

I would like to build one of theses for a project for my AP physics class but I need more detailed directions on how to make it. I mainly need to know what it was that was connected to the alligator clips.

The thing connected to the nails probably generated heat to ignite an alcohol air mixture. It was just a nice little explosion with expanding gas as a byproduct of burning the alcohol. This would be similar to what happens in an internal cumbustion engine, where exploding gas drives the pistons.

I don't know the temperatures for sure, but you can get electric ingniters from a model rocket supply that would probably work and can be run off a battery. I expect they would get hot enough to ignite the mixture.

 

[thepatientmental]

Wow, that sounds like a really cool demonstration! It seems like you may have witnessed a model of an internal combustion engine, which uses a controlled explosion to power a piston. The methyl alcohol in the bottle represents the fuel, and the alligator clips connected to the nails act as the spark plugs that ignite the fuel.

To make your own version of this demonstration, you will need a few materials. First, you will need a glass bottle with a cork that fits tightly inside. You can use a small glass bottle like a spice jar or a test tube. Next, you will need two nails or metal rods that are long enough to stick out of the sides of the bottle. These will act as the spark plugs. You will also need two alligator clips and a small electric grill starter or a similar device that produces a spark.

To assemble the demonstration, start by filling the bottle about halfway with methyl alcohol. Then, insert the two nails or metal rods into the cork, making sure they are spaced evenly apart. Next, attach the alligator clips to the nails, making sure they are securely connected. Finally, connect the other end of the alligator clips to the electric grill starter.

To perform the demonstration, make sure the area is well-ventilated and that you have proper safety precautions in place. Then, press the button on the grill starter to produce a spark. The spark will ignite the methyl alcohol vapor inside the bottle, causing a controlled explosion that will blow the cork off the bottle.

I hope this helps you recreate the demonstration for your AP physics project. Just remember to always exercise caution and follow safety protocols when working with flammable materials and electricity. Good luck!