# Water transport system

## Main Question or Discussion Point

need ideas for a contraption that will transport up to 10L of water across a 3 meters on a counter surface.

Further Design Considertions:

No kits or animals may be used.
Propulsion device that you design make must made from simple compoents such as springs, elastics ect.

Device may not be attached to the table by any clamp or glue, etc.

No energy may be input by the operator other than the one stored by the device. The operator may cut a string, or flip a switch.

No rockets permitted
No chemical reactions or explosive reactions.
No air compressors or compressed air, CO2 cartridges.
No electricity (batteries, and simple electronics are ok.)

Not asking for a complete project here, but just some ideas on how to make it move, and work.

We already have a couple of ideas, but looking for more.

Thanks.

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berkeman
Mentor
Store potential energy in a mass held high, and let the mass drop to transfer energy to an axle between two of the wheels on a 4-wheel cart. In fact, use the dang water jugs as the weight! Make a platform to hold the water, and make it so you can lift the platform up and wind up a cord around the axle. When you release the platform, the weight of the water jugs pulls on the cord, which provides the torque to turn the axle. Bet you get extra credit for using the water to propel itself.

Thats exacltly what we had in mind.

After it accellrates, its goes 3 meters. as it hit 3 meters, somehow the wheel's get locked, and the "tub holding the water balloons" is tipped over, and as a result all the water baloons falling into the bucket.

Danger
Gold Member
Or you could take a 50-litre can and attach a nozzle at the 10L mark from the bottom. Let the jet thrust of the water move the cart forward. The 10 litres will still be there when it hits the finish line.

Last edited:
berkeman
Mentor
affans said:
Thats exacltly what we had in mind.

After it accellrates, its goes 3 meters. as it hit 3 meters, somehow the wheel's get locked, and the "tub holding the water balloons" is tipped over, and as a result all the water baloons falling into the bucket.
Well, you need some kind of derailler (sp?) or other way to disconnect the cord from the axle when the water gets to the bottom of its travel. Just put a slot in the axle or something similar, and feed the end of the cord through the slot a little, then friction lock it with turns as you pre-wind up the cord by turning the wheels. So when the cord is mostly unwound from the axle near the end of acceleration, it slips out of the slot and you coast.

anyone else have ideas?

mouse traps make great short trip stored energy.

Office_Shredder
Staff Emeritus