How do you get a kite to fly?
458745
As the one man stated you need some wind whether it is blowing hard on the day you want to fly the kite or a gentle wind blowing that is above the trees.   Once you have the wind then it is the technique of how to make it fly.   If you have a friend, you will have them to hold it level and as you start to run they can help toss the kite in the air which will give you a little advantage to get the kite started.   As you run you will let out some string but do not try to let it out too much until you start to catch some wind  Once you catch the wind on the kite you can start to let the string out as far as you want but be careful due to if the wind start to stop blowing , you will need to start winding in the string and moving to catch a different gust of wind.  If you do not your kite will start to float down and crash.  Now with one person it is a little trickier.  Some will let it lie on the ground and try to get it off the ground but I like to start to run and let out the string just a little and try to catch a gust of wind that may be a little lower to the ground. As far as lift off with one person do the same as the two person but with a little less string and then as you run you will create that underdraft on the kite and start to let it out but if you let it out too much you will not get it to fly due to the more string you let out the faster you have to run to still create that underdraft to keep the kite flying....
545274
If you have the education to spell a word like pseudoscience, you should be able to fugure out the answer to that one yourself.  My theory is that string is used best when flying a kite.  Maybe you should go fly one too.
885871
Have an elastic material such as a rubber strap and a really firm Y-shaped material. (Any material will do, as long as it is not brittle or liable to snap).\nAttach the strap to the ends of the material and you get your catapult. For greater ease when using your catapult, find a rubber strap that is broader at the centre. It ensures a better grip on the stone/ball/whatever.\n\nHope this helps=)
532453
Because it couldnt fly
1108739
first try to do it on grass or carpet when u r con4table with that go to sk8 parks if u need any more help give me yo e-mail aderss i'l send u a video by tony hawk they show u how to ollie
607417
you can pin it to the frame and wind it around the axle by pulling it backwards, you can use the "propeller" method. basically a balsawood plane with wheels and no wings. Or you can use the rubber band as a slingshot any of these will propell the car up hill or otherwise\n\n Well...\nFrom the materials list alone, it's clear that this is a "professional grade"\nrubber band project. The #107 rubber band is a 5/8" x 7" size, which can\nstore quite a bit of energy. And you'll need it, since you're climbing a\n16 foot ramp with a load. I'm not sure exactly how you "pick up" a 50 gram\nload, but I'll assume that it's suspended over the track so that you don't\nrequire a mechanism to grab it, just drive under and it falls onto the tractor.\n\n\nThe problem then is that you need to balance your gear ratio against the\nweight you have to carry. At the start, you can afford a higher gear ratio\nbecause you don't have much to carry. As you move, you need to "gear down"\nto pull the heavier load. If you just gear it low to start with, you may not\nhave enough travel distance to make it to the end. If you gear too high,\nyou won't be able to pull the heavy load near the end.\n\n\nI'd look hard at a stepped-drum variable transmission. If your drive axle\nhas a series of stepped drive drums, with the smallest unwinding first, then\nyou have a high gear ratio for the first stage that goes far enough to pick\nup the first weight. It then steps up to *just enough* bigger that it can pull\nthe weight, and continues to the second step. Another step up just before\npicking up the next weight, and so on until you reach the end. You use up\nmore rubber band travel at the lower gears near the end, but you've saved\nthe travel during the early part of the pull.\n\n\nI'm thinking that your four feet of string will suffice for the drive system,\nso long as you can can stretch the rubber bands from a support at a distance.\nYou should measure the maximum stretch you can get from a rubber band, and\nfigure from that how much string to use, then use that to derive the drum\nsizes, then take *that* and work out the wheel diameter. If you get a choice\nof "string", I like 90lb test braided dacron fishing line. It's light, easy\nto work with, and much less lossy than cotton string. One option might be\na "boom-style" string puller, with the string attached to the end of a rod\nthat pivots at one end, and the rubber bands anchored to a sturdy structure\nthat pulls the rod. You can vary the attachment points of string and rubber\nbands to get the best balance of pulling force and stroke length, but you\nneed to make sure there won't be overhead obstructions on the track.\n\n\nEfficiency is important; do the best you can to make things smooth, be\nsure there's no binding in your bearings, and look hard at energy losses\nthroughout the system. This is an energy-management problem really, and\nyour task is to take a limited energy supply from the rubber band and spend\nit wisely to *just* achieve the goal. If you can, design your rubber band\nanchor so it can be adjusted, and do your prototype test runs with the\nband stretched to about 70% capacity. That gives you some margin for\nvariables, when the real test comes.\n\n\nHere's a pick of a simple design http://www.balloonhq.com/balloon_car/27.html, here's another pic http://www.plumcreekmarketing.com/07science/01images/fullsize/164304.jpg and another pic http://www.marshall.edu/lego/ati/ATI_LEGO2.htm
241643
A very simple method would be to take a rubber band and anchor inside the body of the car on a hook and stretch it the length of the car and out the back (if you want toe propeller to push) or out the front (if you want the propeller to pull).  \n\nGet a propeller and attach some kind of hook to one side of it (a hook or loop, could even use flexible wire).  You'll need someway to keep the propeller from getting stuck, so you'll want to hold it away from the body using a bushing or other method).\n\nOnce you've connected the rubber band on both ends, just turn the propeller to twist the rubber band, and release to cause the propeller to turn.\n\nThis is simplistic, but gives you a general idea.  You'll of course have to have wheels, and a good method of reducing friction on the propeller and shaft.
298792
It's been forever since I've done it, so I can't give you an actual schematic (try a search engine for that.) I will give you some tips from my science olympiad glory days, however. I assume you're trying to lift the most weight?\n\nMake your sails out of the lightest material possible and with as little re-enforcement as you can get away with it. That way the energy going into turning the sails is minimized and they can rotate faster (and hence do more work.) Depending on size, posterboard or even paper with a balsawood backing usually works well.\n\nDo you know what will be turning the windmill? If it's a fan, try to find one like it and test against that. If you're using natural windpower, this will be harder to do. Only re-enforce the sails enough so they won't get torn apart.\n\nAs far as the string lifting the weights goes, friction is GOOD. You don't want it slipping and costing you energy and time, if time is an element. In all the other elements, friction is BAD. Break out the ssandpaper if necessary.\n\nAll of this is probably common sense, but I hope I did some good. Best of luck.
862527
Compare the tiny water droplets that form clouds to a kite...\n\nWhen a kite has enough wind to fly... it flies... when it doesn't, it falls....\n\nJust be thankful we don't have to shovel kites in the winter!
1122347
1. Set your feet up like you would for an ollie.\n \n2. Place the ball of your front foot toward the middle of the board and slightly below the front bolts.\n \n3. Hit your tail as you would for an ollie, but instead of dragging your front foot up the board, drag it toward the side of the board with a flicking motion. The faster the flick, the faster the flip. It's all in the ankle.\n \n4. Stay over the board as you are jumping and the board is flipping (it's important not to push down on the board once you're up so that it can continue to rise).\n \n5. Let the board hit your back foot once it has flipped completely. This is called catching the flip. Your front foot should not be far behind in getting back on the board, but the back foot usually catches it first. This allows you to control the trick on the way down.\n \n6. Land with your feet as close to the bolts as possible.\n \n7. Do another one.
434974
not at all - just most wakeboards are slightly lower volume than beginners kiteboards so can be a bit harder to start with.\ngood for higher winds though.
428173
Built a trebuchet.  Use your cup to hold the weight (water).  The cup goes on one end of the ruler (throwing arm) and you will need a sling on the other end.  The sling holds the baseball.  You'll have to build a strong frame (more rulers) to hold the throwing arm up.  The frame has to be tall enough to allow the weighted cup to swing down without hitting the ground.  The throwing arm should pivot on the frame.  The pivot point should be closer to the weighted end to produce more thrust.  The length of the sling affects how far and how high the ball will go.  One end of the sling must be firmly attached to the long end of the arm.  The other end must be able to slip off of a smooth nail (also attached to the long end of the throwing arm) that has a small or non-existent head.  The angle of this nail affects the height and distance your ball will be thrown too.\n\nWhen cocked, the weight is up and the tip of the arm is down.  The sling holding the ball is tucked under the throwing arm.  The end of the throwing arm is held down.  When the arm is released, the weight swings down, drawing the throwing arm up, dragging the sling and baseball behind it.  The sling slips off of the smooth nail, releasing the ball.
516448
Sails can go against the wind but not ireactly into it. There is about 90degrees, 45degrees either side of the direction that boats with sails struggle into.\n\nThe sail is shaped much like an aeroplane wing and it is this shape that forces the air to move fater over one side of the sail than the other, decreasing air pressure on one side of the sail and pulling the boat along. This will pull the boat in a slighlty side on motion to the desired travel but a central board (dagger board) creates sideways resistance and forces the forward  motion to be dominant.
548790
this is a websight with great pictures!\nhttp://www.molokai.com/kites/20kidskites.html
580652
So, a boomerang is just two wings joined together at an angle.  When you throw it, you want to be facing approximately into the wind, and hold the boomerang vertical.  If you throw it horizontally like a frisbee, it will climb, and then return very fast, a couple of feet off of the ground.  Not what you want.  When you throw the boomerang, throw hard, and snap your wrist to give it plenty of spin.\n\nNow, when the boomerang is thrown, the wings will rotate rapidly through the air, providing "lift" and making the boomerang fly in a loop out and back.  Ideally, the boomerang will then flatten out and hover to the ground, so you can catch it.  I've never been able to do this part.\n\nDesigning a boomerang is not a hard problem.  Just make sure the "arms" have enough of a wing shape.  Other than that, the design is pretty robust-- you can make them lots of different shapes, and they'll still work...
421842
If you use a fishing pole and line, the kite goes up with little effort or running and you can guide it through any obstacles, too.
520077
Have you tried the Pressurised Bottle Rocket?\n\nEasily constructed with used plastic bottles. What you need is a pump, cork and a tube. Build some tail fins to stablise the rocket for flight. You need to put in some water in the bottle. Then just pump the pressure up and you have an entertaining setup.\n\nHave a challenge who can shoot the highest and then parachute the Rocket down. The highest and/or the longest hang time wins.\n\nYou will need a field to do this properly though.