Hey Ray! Visualizing The Coanda Effect

PITTSBURGH (KDKA) -- Have you ever poured something from one cup into another only to have the liquid seemingly stick to the side, making a big mess? You have some pretty cool science to blame for that!

Moving fluids have a tendency to stay attached to curved surfaces. This is called the Coanda Effect. You can see that the cup's lip is curved enough to allow the Coanda Effect to work. On the other hand, if the cup or container's lip is sharp, the water will pour as you want it to.

Now, we are going to use this knowledge of the Coanda Effect in a science experiment with a different fluid. Air!

Remember not all fluids are liquids. A fluid is a substance that has no fixed shape and yields easily to external pressure. Gasses, like air, fit that description.

We are going to use our knowledge of the Coanda Effect to blow out a candle through a bottle. This is an experiment that uses fire, so make sure a responsible adult is around if you try this.

We know that moving fluids like to stick to a curved surface. Since air is a fluid, it should act the same.

You can see by the fog, how the air sticks to this bottle when you blow across it. Since the air is following the curve of the bottle, we should be able to blow out a candle through a bottle using the Coanda Effect!

Simply, light the candle and put a bottle between you and the candle.

Now, just like a birthday candle, blow it out through the bottle! This even works with more than one bottle between you and the candle, if you try hard enough.