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New Speed Contest Coming Tomorrow Answered

New speed contest to be announced tomorrow. Hint: You don't need a hint.


we already answered that on your how to build a coil gun thread.

correct me if I'm wrong: The nail head makes the magnetic flux no act upon the nail as well. Something to do with pointy shapes?

thats one of the three reasons: 1) the head of the nail causes bad contact between the nail and the barrel, causing loss of power and pad aerodynamics 2)the head of the nail keeps the point aimed down, causing accuracy problems 3) the point of the nail adds mass without adding power. its like you build a 3 engined rocket, but can only afford fuel for 2 engins. on takeoff, you have 3 engins, but only 2 are working. youd have to cut off the head and point to make it work.

I hope it involves nails.


10 years ago

Alright, just making sure. Plus, you can calculate anything with Google.


10 years ago

Just type: (insert number here) m/s to fps in Google.

Dammit! I'm going away in a few hours - does this mean I have to give another idea away?

Sure, I could use some ideas....;-)

Neato! Now that all my school projects are done, I might be able to actually do this one!

... what state do you live in? My school just finished a bunch of projects today...

Washington. I doubt anyone here goes to my school though.

no. what part of

a nail is not a functional shape for a coil gun

is causing confusion?

maybe, I've never actually made a coilgun, just did the research

it depends on the mass and the material of the nail.

This is what we're learning in science class now, yay


F = ma Newton's second law of motion. There are a few assumptions in that "law". #1: notice that it is accurate "only" in a resistance-less world. That is, once an amount of force is applied, the same energy does not "keep" the object moving, but continued force must be applied (in the real world, if not in outer space).
#2: nothing it taken into consideration concerning mass/energy exchange, in this equation. Unlike "relativity" and quantum mechanics, Newton's equation is very un-real. It is accurate, in the given circumstance, but not in the observable world.

Now don't confuse the poor boy! ;-) Newtonian physics is accurate enough that it took an Einstein to figure out how to correct it...

Um, well I guess I should thank you for that comment. :-) I thought it looked funny too so that is why I researched it. ;-)


10 years ago

What time in GMT? =D

Like joejoerowley said, it may have to do with speed. Because he said we don't need a hint.

Ooh, I'd certainly love something wood-themed. Even if this contest doesn't involve wood, the next one has a good chance of doing so due to all the wood related comments.

I hope

I hope its wood related...

Wood would be good, I had to do some wood bashing today after my dynamics test, my sanity was at stake, knocked together a nice little project, it'll end up a slide show.

Im hoping for a food related one, cuz i have a recipe that i think shall go over well on this site...

I am sorry, I am not sure I understand what you are asking.

I'm sorry, I missed something there. I gave a link (my post below this one) to a m/s to fps converter, but it doesn't figure out to the last decimal point. If I understand your question correctly, if the wire is insulated / coated, any further insulation may reduce inductance i.e. output.

I think it has to do w/ speed maybe. Just a guess. God I hope it is really fun and there are awesome prizes. (Not that there are not normally just like total wicked prizes-like laser cutters for all that enter:)

Yay!! *prays to four deity's for a weapon related contest*

The converter is not as accurate as doing it yourself however...

IIRC 1 Meter per Second = 3.28083989501312 Feet per Second, soooo, if you had say 10 m/s that would come out roughly to 32.8(083989501312) fps.

If you need the answer but don't need the equation, this link works too :-)


1 M = 3.2808399 feet
so 1 m/s is the same as 3.2808399 feet per second
the / in m/s stands for per, so it'd be meters per second

so inconclusion, to convert m/s to fps just multiply the meters per second by 3.2808399

is that meters per second or "miles per second" ? ooo, that would be fast...I guess not eh ?


A speed contest and a website conference in Boston? Yeah... no.

Well, I've been loaded down with homework, pressured into learning german at high rates (cramming about 1 and a half weeks worth everyday), working on many projects for school, preparing prjects for states competition for TSA (technology student association), learning how to weld at school so I don't have to rent a welder so I can make my cnc machine, and more stuff that I can't remember, and that's a bad feeling.

I don't know If I should be happy or not, I have so much more important stuff to do... but it's instructables... I'm torn.