Steven asks…
Can someone please give me an idea as to make a ball move without touching it?
So my science teacher has given us an assignment to make a small ball move across a table without touching it. We’re not allowed to put anything under the ball, so technically I need to make something that would push the ball. He said we had to make a renewable energy source to power whatever is going to push the ball. I was thinking of making something like a windmill to push the ball, but I don’t know how to make the windmill turn with renewable energy. Could someone please help me. And if anyone has any better ideas it would really help! Thank you
adminsta answers:
This is a shot in the dark… But what about a rubber band thing that could launce the ball and be wound back up… Or hooked or something.
________ _____________
………………………../
…rubber band -> ( o <-ball
_____________________
^
tube to hold rubber band
and you would need some kind of way to hook it back…
It's an idea…
George asks…
Anyone got ideas on how to make a cheap windmill to produce electricity?
a smallone to light up a small bulb at night
adminsta answers:
I came accross a new, proven and tested home made wind power system and solar power system which eliminates our electricity bills. It was written by a Renewable energy enthusiasts Michael Harvey the diy called Earth4energy. You can get your copy to save energy and help environment while eliminating your power bills. Get the limited special edition of “Earth4Energy Guide + Complete DIY Video Instructions” from here:
http://How-To-Build-Cheap-Solar-Energy.info
Richard asks…
how do i make a windmill lift as much weight as it can?
i has to be 1 meter or smaller in hidth.width and length
it has to be smaller than a meter in hidth,width, and length.
i ment hight
adminsta answers:
You want to use a reduction gear to reduce the RPM of the windmill at your take-up reel. The more reduction, the more torque you’ll have at the reel, and the more weight you can lift.
However, there are diminishing returns. Each gear you add will also add friction, and this will take away some of the windmills power. With enough gears, there won’t be enough power available to move the gears, much less lift weight.
Also, the more reduction, the longer it will take to lift your weight. Even if you don’t use up all your power with gear friction, you may not have enough time to lift your load if there is any kind of time constraint.
Sandra asks…
how much electricity can a capacitor hold?
Is a capacitor like a battery? For instance, is there a short burst, or a stored amount that is slowly discharged?
I was wondering if small windmills/ fans/rotors, maybe attached to the back of a moving car, could provide enough energy to be useful somehow. Would a sustained 120volts be possible for a short time? How can we make use of movement, even if its in small amounts, like air blowing into a moving cars engine compartment as usual, but have it turn a fan motor located inside, which would be hooked to a capacitor. The fan shouldnt cause any power loss because it wouldn’t have drag, and could even be useful in cooling off the engine. It just seems like there is wasted potential and energy out there.
Thanks for all the great answers. Seems like batteries would be better for the applications I mentioned. In which case, electric cars or their owners, probably have already applied this to charge their vehicles. Maybe I will work on flashlight batteries instead..lol or an electric AC for all cars or something
adminsta answers:
To be specific, a capacitor stores charge. The rate that an ideal capacitor is discharged is entirely dependent on the circuit it is connected to. An equation that describes the electrical behavior of a capacitor is I=C*(dv/dt) where I is the current into or out of the capacitor (think of current as the movement of charge), C is the rated value of the capcitor (a measure of how much charge it can store) and (dv/dt) is the rate of change of voltage across the capacitor.
While it would be possible for an appropriately constructed capacitor to be charged up to 120v. It would only sustain 120v as long as no current was flowing. In order to make use of the energy in the capacitor, charge must leave the capacitor, thus current must flow and the voltage will change. In practical circuits, a capacitor that needs to store energy in this way would need to be chosen with a large capacitance (storage capability) that the change in voltage when current is flowing is acceptably small for the given application.
The key difference between a battery and a capacitor is that a capacitor stores energy strictly in an electric field while a battery stores energy chemically. In general, more energy can be stored in a battery of a given weight, volume, and cost, than in a capacitor of similar proportions. Also, real world, non-ideal batteries and capacitors slowly dissipate energy through internal paths even when energy current is not flowing out of the device to do meaningful work. Again, batteries typically outperform capacitors in this aspect of storing energy, although new technologies are constantly being studied for energy storage in both types of components.
Nancy asks…
Solar panelling and thatch?
Hi, I’m fifteen and thinking about how to make my future house eco – friendly so obviously solar panels, but they’re really ugly so would it be possible to have thatch covering it over or would it catch fire? (I’m talking about the roof obviously).
Also is it possible to have a small windmill for your personal house use as my country is more windy than sunny (Ireland)
adminsta answers:
Yes, you can use a combination of solar panels and windmills
Helen asks…
Palm Trees, Grow from middle?
Is it true that palms grow from within, like as in, the prongy things grow from the center of the trunk. hmm, let me help this make sense. so I bought a small palm, and two huge ones. the smallone is a windmill and the one i want more info on. It has say five ‘prongs’ (is that what they are called?’) and Where will the new ones form. I heard that they do not grow out of the side of the trunk like a branch, but that they are more like, hmm say a flower bud? Like the things grow from the very middle and sprout upwards? The guy who helps take care of my garden cut some of the prongs and I want to make sure there will be more. I understand the trunk will grow, but how does it get new prongs. Sorry if you have to reread but i couldn’t make it any more clear… need more coffee i suppose!
=)Thanks for any help!
adminsta answers:
Yes, the new palm fronds grow from the middle.
Sandy asks…
Do Nike Hyperdunks runs true to size?
I am planning on ordering a pair of Nike Hyperdunks. Usually when I buy shoes, i find them in a store to try them on, but no stores in my area carry them. I want to make sure I get the right size, because I am getting the hyperdunk id’s and can’t return them if they don’t fit.
I wear a size 10 in most of my shoes:
size 10 in nike flight windmill‘s
size 10 in nike zoom flight 95′s (jason kidd)
size 10 in nike s.t.a.t. (amare stodemire’s)
size 10 in nike air uptempo x
but my nike air insurgents are a size 10.5
my friends that have told me they run a bit small, but they said it was up to me how i wanted them to fit, and that i could always lace them up tight. i think i should order size 10, as most of my shoes are, but i don’t want them to be too snug.
So should i stick with the 10′s or go with a 10.5? thanks
adminsta answers:
Always go the bigger size. Go with the 10.5. They will either fit or be a little big. You can always wear two pairs of socks or an ankle brace. You should wear two socks anyway so that you don’t get blisters and protect your feet and ankles. If you get too small to start you can’t go anywhere but returning them.
Paul asks…
NEED TO STORE ELECTRICITY AND AT THE SAME TIME USE IT?
HELLO
my son has a school project .
i need some thing that i can in put electricity (small v ) in to the batteries and at the same time use the electricity from the batteries . i cant just put a paterie and conectit to both of them beacause the in put is a wind mill (small scale ) so if i do that it would just run the windmills motor .
what is the name of that thing ?
and how can i make it a home ? ( if i can )
and some guy on internet sed that you cant do that.. i know 100% that its posible to d it. laptops use it ,windmill , phones, lot of devices use it.
adminsta answers:
Better than a diode, use a full wave bridge rectifier. You will be able to buy all four diodes packaged into a single unit with four terminals and probably cost under $1.
Http://en.wikipedia.org/wiki/Bridge_rectifier
The current will only ever flow into the battery, even if the wind stops. It will also charge over the maximum possible part of the cycle.
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