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A Tub Toy for Teaching Electricity

A water based toy for teaching the principles of electrical circuits, without the use of electricity
  [vote for,

It turns out that not only adults like playing with toys, but kids like them too. What I will describe here is my jab at the all too elusive goal of having kids learn REAL science while having fun playing. Specifically, this toy will use intuitive concepts of water flow to demonstrate, by analogy, not-so-intuitive concepts in electrical flow. This is fundamentally different from common electric set, that have elaborate projects, but almost never explain to you what the components really do and what is actually going on. I’m not sure what the best age groups would be for this, but it is likely that even science inclined mid-teens would find this toy fascinating as they get a better appreciation for the physics behind it.

In essence, this toy would be similar to Capsela construction kits (see link), but instead of the capsules containing rotating mechanical components, they would contain plastic tubing, watertight membranes and valves. All of which would be transparent or semi-transparent, so you could see their inner workings. In addition, you would have a standard sized connector or tubing for connecting the capsules together. Because you’ll inevitably have water squirting all over the place, it is best to play with this toy in a tub or open yard. With a little bit of ingenuity, it may be possible to have open ends automatically seal themselves and prevent too much water from gushing out.

Some of the components you would have:

Resister – a capsule with a thinner tube in it

Switch (variable resister) - a capsule with a valve that can be set by hand

Capacitor – a capsule with a flexible rubber membrane dividing it in two

Inductor – a capsule with a small fan geared to a flywheel inside

Diode – a capsule with a one-way valve

Transistor – a capsule with a valve pivoted by a third water entrance

Battery – a large water balloon

Generator – a hand cranked in/out water pump

Ammeter – a water flow gauge

Voltmeter – a water pressure gauge

Put together you could build anything from a flip-flop to a logic gate. Though just like Lego, I’m sure most kids will enjoy it just as much without a grand project in mind.

imho, Mar 02 2009

http://en.wikipedia.org/wiki/Capsela [imho, Mar 02 2009]

Bells & Whistles explains their water powered computer's logic to Mr. Crunchly http://www.catb.org...ml#crunchly74-12-25
[Spacecoyote, Mar 02 2009]

Hydraulic analogy http://en.wikipedia...i/Hydraulic_analogy
[xaviergisz, Mar 02 2009]

US patent 6773265 http://v3.espacenet...le=en_EP&CC=US&FT=D
Electronic simulator [xaviergisz, Mar 02 2009]


       sweet. I have never heard of anything like this.
bungston, Mar 02 2009

       Part of the hacker culture comic strip "Crunchly" dealt with water powered logic [link], there was a whole saga.
Spacecoyote, Mar 02 2009

       Sounds good, But I imagine most of the parts have to be fully loaded without bubbles to work . It still would not explain the field between charges .
wjt, Mar 02 2009

       What no memristor? Interesting, but you'd need something to get the water in the capacitor maybe Goretex valves to let the air out. Or if there is a standard "up", floaty ball check valves would work. Also the balloon/battery is bad as no circuit is made.
MisterQED, Mar 02 2009

       Didn't we do this a loooong time ago?
phoenix, Mar 02 2009

       Nice [+]. There used to be something called 'fluidics', which used the flow of liquid in devices acting as logic gates. It was most popular around four decades back, and was used in factories, drills, sewing machines and notably in the manufacture of the roof lining of the Hillman Imp. It was also used in a paper mill in Aberdeen to find the edge of rolls, to fill detergent bottles in a factory in Dublin and to de-ice fishing vessels and various other things. They work at the speed of sound in the fluid used.   

       Components in fluidics include logic gates and other things called vortex amplifiers, wall attachments, jet interactors and turbulence amplifiers.   

       I'm afraid i know very little about them, but they certainly did exist. Don't know about now. Some of them were manufactured by Plessey.   

       You could probably find some info about them on that internet thang, but i've never bothered to look.
nineteenthly, Mar 02 2009

       electricity doesn't leak, and water doesn't need a complete circuit to flow. How is this any better than a "my first circuits" playset? The parallels between the two are very weak.
WcW, Mar 02 2009

       //electricity doesn't leak//
<raises eyebrow quizically> Really? </req>
AbsintheWithoutLeave, Mar 02 2009

       does a "leak" complete a circuit? What about induction: water doesn't do that.
WcW, Mar 02 2009

       //does a "leak" complete a circuit?// Of course; it returns to earth.   

       Of course, the downside is that it may encourage Junior to play with real elastic-trickery in the bath.
AbsintheWithoutLeave, Mar 02 2009

       //What about induction: water doesn't do that.// Induction would be condensation. Look up "solar still" to see it in action.   

       I guess a leak would be electromagnetic interference or something.
Spacecoyote, Mar 02 2009

       Re: fluidics.   

       You'll find that pneumatic and hydraulic logic are still used in certain areas of industry. For instance, we use a certain brand of pneumatic "suck-and-blow" type sump pump here (notice me skirting around using brand names). The control circuitry that determines the phase timing is completely cascade logic. That's right - little pipes and actuators and accumulators, etc.   

       There are also still hydraulic systems that utilise cascade-type logic to perform simple tasks. In fact, it's not all that uncommon at all. Back at uni we had a modular set of pneumatic widgets that they used to teach us cascade logic, which was a major component of one of our subjects. I remember designing and making crude machines that ran to the regular psssst, whoosh! of the pneumatics at work. Loverley stuff. This was all part of our control systems subject, to illustrate the way that simple cascade logic can be rationalised into more complex logic circuits, using a mix of standardisation and innovation.
Custardguts, Mar 03 2009

       BALLOON? If a battery is a large balloon, then so is a capacitor. Batteries don't store charge any more than capacitors do; batteries are like constant-pressure pumps.   

       To change a 2-chamber membrane "capacitor" into a battery, just use a larger chamber (more farads,) and replace the rubber membrane with a piston, with a constant-force spring to provide the Pressure Difference. Pump charges backwards through it in order to "charge" it up.
wbeaty, Mar 03 2009

       but when you try to make the model work suddenly you realize that it isn't much of an analogy. I really confuses the kiddies when they try to reconcile the differences. So profound is the confusion that this causes that I actually unteach these ideas before trying to explain how anything electric works to a child.
WcW, Mar 03 2009

       If you do not get shocked how will you remember?
vfrackis, Mar 03 2009


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