Pascal's Blaising Barrel - Exploding Glass Barrel with Water Pressure

How can the water pressure created by 1 liter of water burst a 50-liter glass barrel?

Watch this video to find out! This is the first time in history (as far as we know!) that this experiment was successfully done, even including Blaise Pascal himself!

Clarification (since a lot of people commented on this): The pressure created inside the syringe did not have any effect on the pressure in the tube/barrel, since the tube was open to the atmosphere at all times. At 3:50, you can see how I used the syringe like a funnel, just to get the water into the narrow opening of the tube. I made sure to never block the opening of the tube entirely, and the gap is visible on the right side of tube opening. This gap allowed the air in the tube to escape as the liquid entered it, and thus ensured that the pressure inside the tube remained at atmospheric pressure.

For those wondering why we didn't just use a funnel - we tried that, and the liquid blocking the opening caused even more air bubbles to get caught in the tube. After some trial and error we realized that we needed to pour the water into the tube very slowly, and the best solution we came up with was to use a syringe.

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[tedzusa]

The best part of this video was keeping in the mistakes, and showing that science isn't always perfect before it goes into the textbooks.

[msg]

Another way to think about pressure depending on only the height of the water is to go to the edge of a lake, dig a small hole, make a channel connecting the two that's only a few centimeters deep, and then try damming that channel with your hand. The force of the water you're trying to hold back will feel negligible, even though there's a massive amount of water on the lake's side.

[procrastmh]

This was the only video I found about the topic. Thanks!

[friendsbrn]

Great demo! Honestly though, I think my favorite part was the bit about the technical challenges of this experiment - thank you so much for including that.

[fargo]

I love this professor. She's great and I can see how much fun it would be to learn in her class.

[Madnikodemus]

Fantastic experiment. That’s a real teacher right there.

[Marcosticks]

When you search the world for something that someone should have done long ago (and documented), but you find nothing... then you know you have got a gem. Cool video. I admire your perseverance.

[DanildFlamme]

That is so cool... I knew the physics of it, and understood that it should work, but it is still REALLY fascinating to see that thin tube of water breaking that big glass, purely because of the height of the water "column".

[TheJagjr]

I enjoy hearing her lectures and experiments, her voice is very pleasing to the ear.

[MottiShneor]

A really GOOD demonstration of a physical law/property. You can learn Pascal's law a hundred times, and even pass exams using it and its mathematical equations - but this short explanation followed by a pin-point "query to Mother Nature" with such a thin - even flexible tube, and so little extra water - will really do the job. People who watched this video will have the fact and physical law "nailed down" in their heads, part of their future intuition. 

I admit to have been surprised, despite my BSc. in physics (ok, from 40 years ago...) my Intuition had it that the AMOUNT of water (hence its weight) had to do with the hydrostatic pressure. I really needed that reminder of Pascal's law and its meaning. I learned something here.

Thank you.

[stepbystepscience]

Amazing, thanks so much for doing this and then sharing it with the world.

[eljefeamericano]

Thanks for going to all of the trouble to make this demonstration! It's great to actually see a lesson, and not just learn it and accept it's probably true.

[stomp]

The only demonstration i could find online... Thank you!

[philip]

Great experiment and very well executed! You did a good job dealing with all the challenges.

[maini]

Super very nicely explained and demonstrated. This type of videos should be shown in schools.

[clairecelestin]

I'm really glad you had the foresight to dye the water in the tube. Notice that as soon as the vessel fails, it starts to fall, and the top of the vessel accelerates downwards at the expected 1 g. However, blue water immediately sprays in even faster than a simple 1 g acceleration from gravity could allow. This shows that the water has forces acting on it other than simple gravity- in particular, the spring-like elastic deformation of the tubing, and to some degree, the water itself (even though water is carelessly described as "incompressible", it does actually compress a very small amount). Without these forces, the top of the vessel and the blue water would have accelerated at the same rate and we would not have seen the blue puff.

[jamesforgington]

I’ve never been so enthralled by an educational demonstration in my life

[宇戸名地味朗]

Now I know excitement is another word for science. Thank you doctor.

[mrthingy]

I wish we'd had experiments like this when I was in high school (a long time ago). Seeing physics and mathematics in action really helps.

[stevenpurtee]

I've been using this video in my Physics with Calc college class for a few years. Now I'm going further and using it as a Canvas video quiz.