with only 6 volts of power can only use c and d size batteries. homemade switch and battery holder must stay lit for 1 minute. brightness of 1 candle. and i have to construct the filament. please help
215147
either your teacher is nuts or you probably know more about this than us. the bulb has to be a vacuum, and making a glass vacuum requires better equipment than most people have access to.
156641
atach a wire to each part of the batter, attach them to the light. create a circuit and you will have light
324487
if u know how to build a cricuit i can explain you .!!!!\n\nbut if u dont know how to make a circuit... u r in wrong way ... u probably need to learn circuit making... or better yu buy a remote from a shop ;-)
498576
Depends a lot on the type of bulb but assuming an incandescent it would be virtually instantly. Remember from physics that the electron current  velocity does not have to be very high at all because what is actually happening is a displacement of electrons throughout the entire length of the wire. It only takes a few extra electrons per linear meter to produce a rapid displacement of electrons throughout the wire\n\nSorry DW electrons do not travel at C in a wire. That is a bad misconception propagated by incompetent high school physics teachers.
233345
try to prove Ohm's Law. it relatively simple. but of course you're playing with electricity so careful if u try it...or do something on sound(doppler effect), or even magnetism(there are some sick stuff you can do with these) if everything sounds boring try light..experiment with diferent colors and such, or try to make your own laser(hehe..but dont flash it in your eyes)\nwhatever you do good luck
670767
yeah you can use a switch (voltage switch) or if you can use binary logic, need to know how much voltage/current you are dealing with
91530
Not enough to screw in a light bulb.
374221
I'd suggest a minimum 5kW generator.  I can't imagine the sewing machines being more than a few hundred watts operating power, and it is unlikely all five will start up at once for surge currents to add.  There should be plenty of headroom left over for the fans and lights.\n\nVisit my home generator page for other ideas.\nhttp://members.rennlist.org/warren/generator.html
87605
Look up Tesla Coils on the internet, but be VERY careful with these devices. They are high voltage but a cool science fair project.
352356
Here's an idea. Make one that will shock people(low voltage) when they ring your bell. ;-)
623429
A motor is an electrical device that turns electrical energy into mechanical energy. I really don't think that is what you're after. You want to turn mechanical into electrical, right? Okay, in old cars, before they had alternators, they had generators. Snag one of these at a junk yard. It will charge a 12 volt DC battery. I have never done this, I am just theorizing as I type. Anywho, campers use 12 volt DC lighting as a back up. Heck even the fridges run on 12v, propane, NG, or AC. In theory, fabricate blades to this generator, with a voltage regulator and there you go. Actually, here is what I do. I used camping lighting that burns clean fuel and flashlights, but if you simply had an inverter, you could actually run a few things via you car. Another suggestion, a more serious one. Look at the way they make campers so self sufficient. 2 lighting systems, where one runs on AC and the other DC of 12 volt batteries. Not a bad idea for your house? They have there own battery charger, which you could put in your house, that keeps these batteries full whenever you are plugged into AC. Add a 12 volt light system to your storm center, add a camping stove with a small portable tank, vent the area. This stove could cook and serve as a source of heat. Get the fridge that runs on anything, what else do you need? Oh yeah, plans for a wind generator. Dragonfly Wind Generator. That's what you are in need of. Perfect for residential.
234029
Use a darlington array. They make them with 6 or more darlington transistors on a single chip. Some even have the circuit protection diodes built in. These are perfect for stepper motor control circuits. If you don't want to buy them, you can probably scavenge a couple from a dead printer or copier, if you can get one.\n\nOther than that, there is no best transistor. This is a general, low speed switching application, and almost any transistor that can handle 160mA at your circuit's voltage can be made to work with the proper biasing. But a single chip to replace several transistors and diodes will simplify your PCB.
46512
Materials needed:\n     1 lemon\n     1 paper clip\n     1 copper wire (18 guage works well)\n\nProcedure:\n     1.   Straighten out the wire of the paper clip.\n\n     2.   Cut a piece of copper wire roughly the same length\n          as the paper clip.  Remove the insulation.\n\n     3.   Push the paper clip and the copper wire into the \n  lemon.  Keep the wires as close together as you\n          can, but don't let them touch.\n\n     4.   The fruit battery is now ready for use.  If you\n          have a voltmeter you can test how many volts\n          the battery produces.  You can also taste the\n          two wires and feel a tingle in your tongue.\n          (Note: you should only do this for very low\n          voltages such as those given off by lemons.)\n\nHow it works:\nAcids, such as the citric acid in lemons, tend to produce chemical substances called ions. These ions either have too many electrons (negative) or not enough (positive) Metals tend to attact these ions. \n\nOne type of metal will attract the negative ions and the other will attract the positive ions. This causes the two metals to have different electrical charges and electricity will flow from one to the other whenever you attach the battery to something like a radio (or your tongue). \n\nIncidently, the flow of electricity will eventually neutralize the ions. When this happens the battery is dead. \nand also see:
477619
Not sure what you are trying to do but it kind of sounds like you are attempting to replace an arc-discharge light with an incandescent.\n\nThey have fundamentally different drive requirements. The arc-discharge has a negative resistance and it will not operate without a ballast designed specifically for that lamp. Such ballasts sometimes include active power-monitoring. The lamp and the ballast need to be paired with each other. Using a lamp and ballast not designed to work together will result in one of: won't work at all; will have very short life; will have unstable operation.\n\nThe incandescent lamp has a resistance that changes dramatically as the filament heats up and it is therefore self-ballasting. It works best when operated from an approximately constant-voltage source, not a constant-power source.
538109
Sounds like you already have some fantastic ideas!  I personally like the soda can and chocolate bar method.  I have to admit, I'd never heard of it until you mentioned it.  Now, I look forward to trying it.\n\nDon't forget flint.  That's an effective and popular method.\nYou don't necessarily need the 9-Volt battery with steel wool, I've seen it done with flashlight batteries.\nYou can still do the condom and water, just use a clear balloon (if you can find one).\n\nI'd stay away from chemicals for that age group.\n\nHere are some links for you to take a look at...\n\nhttp://www.onagocag.com/fire.html\nhttp://members.cox.net/bsatroop218/skills/nomatch/nomatch.html\nhttp://www.christianhomekeeper.com/fire.html\nhttp://www.fieldandstream.com/fieldstream/outdoorskills/article/0,13199,1149562,00.html\nhttp://www.alpharubicon.com/primitive/firewithout.htm\nhttp://www.bizarrelabs.com/firebow.htm
464521
First, what is the input voltage and the desired output voltage?  Is the output voltage fixed, or do you need a range of adjustment (taps)?  Do you need isolation between the input and the output?  If not, an autotransformer (single winding) might be acceptable.  What is the frequency, and is it single phase, three phase Y, or three phase delta?\n\nNext, what is the power rating?  Small transformers are usually rated in output current, whereas larger transformers are rated in KVA.  This is the maximum load;  a smaller load would not be a problem.\n\nFinally, what are the mechanical factors?  Does it need to be hermetic or can it be open frame?  Do you want terminals or wire leads?  What shape and size?  What is the mounting?\n\nIt's not really that hard.  Usually you can browse through a catalog and find the transformer you need in minutes.
137022
Someone has used a gasifier and captive-piston engine to make a one-moving part alternating-current generator. The piston is magnetized and the coils are in the body of the cylinder. The trapped air in the cylinder at each end of the piston acts as an air shock to eliminate rebound and impact damage. No sensors needed. No make and break circuit. The voltage drops to zero at the end-points of travel of the piston. Search on this and you can probably find the same one I saw. I think this is where they got the idea for those new shake-up LED flashlights.