Hot Experiment

[joe]

Here is a little experiment that should make you go Wow! I discovered it years ago by accident.

What you need:
A regular, dry washcloth
A small bottle of water (Room temperature gives best results but cold water works too.)

Take the washcloth and fold it in the middle, then fold it once more in the middle to make a square that is 4 layers thick.

Open the water bottle and hold the cloth on the top. Just tight enough to keep the water from squirting out the sides when you turn it over.

Turn it over and gently squeeze the water bottle.

Result: The washcloth and your hand will warm significantly for a second. Even the water in the cloth will warm briefly.

I get a kick out of it everytime I do it. I have tried to figure out the scientific principle behind it, with no luck yet. Does anyone else know why or how it warms that much?

Sometimes it gets hot enough for me to drop the washcloth. You can get the same, though on a smaller scale, results using a paper towel folded twice as much.

[unk]

Is that a global warming trick?

[horribilis]

must be your body heat trapped in the layers of cloth. if you squeezed harder your hand would feel the water at room temperature

[gitpikker58]

Actually I think there is something to that. Cold is the absense of heat, and when cold water is applied to the cloth the heat has to go somewhere so you feel it with your hand. I've noticed that before too but really didn't give it much thought.

[joe]

No ploy unk, just a physic question that bugs me.

I agree it seems to have something to do with the stored heat in the cloth. The pressure from the water seems to increase that heat for some reason. It may be similar to the temperature increase associated with atmospheric high pressure. I am inclined to believe that under the right conditions one may be able to generate fire using water and air. I know engines running on water are the claims of less than credible individuals but I am wondering about other possibilities.