ShmoopTube

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We speak student! water wheels are simple put a giant wheel in moving water and [a giant wheel in a lake]

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the water makes the wheel turn boom end of video seriously what are you waiting

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for roll that shmoop copyright screen alright fine it's a little more

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complicated than that especially when we start analyzing energy flow water

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flowing in a river has a whole bunch of kinetic energy thanks to gravity [a very small waterfall]

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dragging the water downhill toward the nearest ocean from a human perspective

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all that energy is being wasted but water wheels are crafty little thieves [a waterwheel disguised as a thief in the fields]

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they steal some of that wasted kinetic energy and make it do useful stuff like

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grind grain saw timber or pump bellows all right why not sit back and let the [woman sitting by a pool with her feet in the water]

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water do all those things can't earn your keep their water because of their

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simplicity waterwheels haven't changed much since ancient times the water

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wheels that crushed grain into flour two thousand years ago had the same basic [a modern day electrical turbine]

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setup as the ginormous turbines producing electricity in China today hey

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if ain't broke you know why fix it however thanks to several centuries of

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tinkering water wheels have a definitely evolved us in a few ways well the goal [a building man tinkering with an electrical turbine]

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was always to make them more efficient the first water wheels were horizontal

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think of a normal water wheel lopped over on its side alright well this [waterwheel on its side in a small puddle of water]

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is a video here just look at it instead well the axle stuck straight up out of

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the water and into the floor of the mill where it turned on millstone there were [

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no gears gadgets or doo-dads that's a shame as we love a good doo-dad [flying toy carrying a man away]

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right well if we're comparing water wheel to cars the horizontal

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waterwheel was the equivalent of the Model T got the job done but boy it [an olden car bobbing up and down as it drives down the road]

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wasn't perfect at some point someone had the bright idea of standing a wheel

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straight up on its edge these vertical wheels were called undershots because

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all the water flows under them brilliant right well undershots were more [waterwheel with a pink line showing the undershots]

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efficient than horizontal water wheels but technically they still only transferred

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about twenty-five percent of the rivers energy to the mill that means [lots of water gushing down the river]

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75 percent of the rivers energy was just wasting away down the river rivers man

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such a freeloader well the main problem with undershot wheels was that they got in

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their own way the river pushed the paddles forward but they lost speed [a wooden waterwheel in a small puddle of water]

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dragging through the water and even more efficient version of the water wheel was

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the overshot which was positioned so the water would run off of an edge and dump

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itself all over the wheels paddles over shots are twice as efficient as under [an overshot waterwheel]

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shot but for hundreds of years nobody knew which model was better because

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people didn't understand the science of energy or have any way to measure it so

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now let's imagine we're medieval Europeans who want to grind some weed [medieval people laying on a beach]

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but we live on the coast not near a river what do we do what do we do curse our

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parents and their beachbum way no well maybe if we get one more message from

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them saying Prithee bring my board wax hither dude irritating messages aside [medieval boy stood on a beach with a blue phone]

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we don't need to do that if we've got a tidal wheel well in coastal areas that

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needed a water wheel ingenious folks built cause ways to trap the water that [a cause way of rocks used to trap water]

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poured in at high tide after the tide receded they release the trapped water

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through a narrow opening and use it to power a waterwheel which then allowed

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those medieval beachbum parents more time to surf gnarlieth dude though if you [medieval parents surfing by the shore of the beach]

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remember one thing from this video let it be this that evil beach bum parents

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are the worst so get your own board wax [medieval parents standing on surfboards as the sun sets]

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