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Oobleck........

(24 Posts)
Katek Fri 21-Oct-16 18:53:58

Was visiting DD earlier and Dgd (aged 10) appeared in the kitchen and took a packet of cornflour out of the cupboard. When asked what she was about to do with said cornflour her reply was "I'm making oobleck." Puzzled, I then asked her what oobleck was to be told that it was a "non-Newtonian fluid" - this is was accompanied by the don't-you-know-that look! Actually, no, I didn't know what it was, but I do now.....apparently police wear it in their stab vests. You're never too old to learn.

Elegran Fri 21-Oct-16 18:57:02

Ooh eck! (couldn't help that, sorry.)

nanaK54 Fri 21-Oct-16 18:58:24

Also known as gloop lots of fun!

Katek Fri 21-Oct-16 19:02:23

elegran grin

Ana Fri 21-Oct-16 19:13:28

But why was she making it anyway...? thlconfused

Katek Fri 21-Oct-16 19:15:40

No particular reason ana ...she just fancied doing it!!

Ana Fri 21-Oct-16 19:19:32

Oh! Right...and why not?

Wobblybits Fri 21-Oct-16 19:24:21

Custard powder does the same thing. I once won a prize on a science phone in radio program for asking about the odd properties of custard powder.

Elegran Fri 21-Oct-16 19:37:52

Does she know that if you put some custard powder into a tin, and close the lid firmly, then shake it up well, stand it on a level surface and retire to a safe distance, it blows the lid off with a very satisfactory explosion?

Wobblybits Fri 21-Oct-16 19:42:04

Put it near a flame and it will bring the ceiling down as well, custard powder (as are many other fine powders) is explosive. best not tell the GC, or they may try it.

Wobblybits Fri 21-Oct-16 19:45:34

If you've not made oobleck it is fascinating.

www.instructables.com/id/Oobleck/

Katek Fri 21-Oct-16 20:14:25

Oooh......exploding custard! There's something a bit Goon-ish about that! Dgd would love to try this experiment, she's a very curious child who loves to know the answers to everything. She can be a bit of a challenge.

FarNorth Fri 21-Oct-16 20:14:39

Thanks for that link Wobbly.

Wobblybits Fri 21-Oct-16 20:32:29

This short video shows how dust can explode. Factories and lives have been destroyed by dust explosions.

www.youtube.com/watch?v=RZLRbVw3RnM

Linsco56 Fri 21-Oct-16 20:59:49

Katek buy some Alum powder from a pharmacy or from an Asian food store then google how to make crystals with Alum. I remember doing this at school and your Dgd will enjoy it.

I didn't know about exploding custard powder grin I'm so going to try this tomorrow!

Wobblybits Fri 21-Oct-16 21:07:38

Check your fire insurance first

Linsco56 Fri 21-Oct-16 21:20:17

Ha ha!...DH suggested putting a lit tea light in the tin before the custard shock I won't be doing that!

Elegran Fri 21-Oct-16 21:22:45

Make sure they ca' canny with the exploding custard. Flour mills were notorious for being destroyed by sudden explosions and fires, caused by the fine dust igniting. There used to be many mills along the Water of Leith, nearly all of them burnt down.

Deedaa Fri 21-Oct-16 22:05:13

Isn't there a theory that the Great Fire of London was actually started by exploding flour in the bakery?

Wobblybits Sat 22-Oct-16 08:28:01

DeeDa, that's how I believe it started. I think it's due to the high percentage of oxygen available to each particle. Try setting light to some iron filings, they will burn easily, whereas solid iron will only burn if large amounts of oxygen are applied, as in oxy/acetylene cutting or a blast furnace.

Aurelia Sat 22-Oct-16 09:12:49

Next time your DGD has ketchup on anything you can tell her that it's a shear thinning fluid! thlgrin

Katek Sat 22-Oct-16 09:51:14

Fluid mechanics aurelia? I will have to go Google!! Dgd will be delighted with another piece of info, but Nanna will need to know what she's talking about for the Q&A session!

trisher Sat 22-Oct-16 11:26:34

My older brother keen to pass on his scientific knowledge gained from his grammar school showed me how custard powder exploded when I was about 10. He also blew bubbles with a rubber hose attached to a gas tap and put a glowing splint into it to make a satisfying bang. We also sprinkled iron filings onto the gas cooker. It was like firework night. I'm horrified now to think what might have happened.
Love oobleck , but we called it gloop!

Jalima Sat 22-Oct-16 12:14:32

One of our schoolfriends attempted to make fireworks and succeeded in blowing three of his fingers off.