Homo Sapiens Vulgaris
You need to be fairly precise in your experimental setup - but yes, you are able to roughly determine the velocity (at the time of impact) by measuring the angular deflection of an object with a known mass.
You'd use two wires to keep said mass rotate around a single axis. If you could precisely measure an arbitrary deflection (regardless of both magnitude and direction) a single wire would be adequate.
It is preferential to refrain from the utilisation of grandiose verbiage in the circumstance that your intellectualisation can be expressed using comparatively simplistic lexicological entities. (...such as the word fuck.)
Remember your humanity, and forget the rest. - Joseph Rotblat
Off the wagon
Originally Posted by Tom
It's not so much the speeling, it's the punctuation...or the lack of. Did the avo cannon die?no, but theres plenty better at spelling
Hardcore Biker
yer i can post some up im in the process of makeing a bolt acton spud gun too.. If you want to increast the killing power hammer a big nail right thru the avo/potato or whateverVery interestng...hmmm got any pics of this Avo cannon?. Ive got a Possum in my roof & as im a Kiwi i reckon im allowed to kill the fucker.Stupid animals are protected here. Would said weapon work on Rabbits too?
Homo Sapiens Vulgaris
The simplest way of making a rough estimate would be to consider the problem from an energy conservation perspective.
The increase in potential energy of your pendulum should be equal the decrease in kinetic energy of the projectile:
dEkin + dEpot = 0
This is pretty rough since some energy will be expended deforming your projectile, localised heating, wind resistance, non-perfect wires, etc.
dEpot = (m+M)*g*dh - where m is the mass of the projectile, M the mass of the pendulum, g the gravitational constant and dh the change in height of the pendulum.
dh = l * cos(theta) - where l is the length of the wire and theta is the deflection angle.
The velocity should then be given by:
v = sqrt(2*(m+M)*g*l*cos(theta)/m)
It's important that you choose the weight of the pendulum carefully in relation to the weight of the projectile. It is also important that the entire projectile moves with pendulum. You need to establish the centre of mass of the pendulum fairly precisely - or use a very long wire.
It is preferential to refrain from the utilisation of grandiose verbiage in the circumstance that your intellectualisation can be expressed using comparatively simplistic lexicological entities. (...such as the word fuck.)
Remember your humanity, and forget the rest. - Joseph Rotblat
Forum whore
Why don't you just post up the whole method of how to make one? With diagrams. And youtube links of it in action. And the police report....?
They shall not grow old as we that are left grow old.
Age shall not weary them nor the years condemn.
At the going down of the sun and in the evening,
we will remember them
One, two free, floor!
Am I the first the raise the requirement for a firearms license...?
As for the velocity, set the thing up to any angle (I'd choose 45 degrees giving max range), fire it, measure the range then click here
$2,000 cash if you find a buyer for my house, kumeuhouseforsale@straightshooters.co.nz for details
i'm motarded
google is your friendWhy don't you just post up the whole method of how to make one? With diagrams. And youtube links of it in action. And the police report....?
a electric bbq igniter is all i used in mine
Homo Sapiens Vulgaris
Nice - but it doesn't take wind resistance into account. If the firing range is decent then the error on that calculation will be significant.
Having half a metre between the muzzle and the pendulum would pretty much give you the muzzle velocity - with less error. The measuring is a bit more difficult though.
It is preferential to refrain from the utilisation of grandiose verbiage in the circumstance that your intellectualisation can be expressed using comparatively simplistic lexicological entities. (...such as the word fuck.)
Remember your humanity, and forget the rest. - Joseph Rotblat
http://rogerfleming-raftnn.blo
The title had me confused.......from then on its all been down hill.
One, two free, floor!
I think close enough is probably good enough on this one... unless ultra long range stuff is going to be done. Avo vs. shipping might be interesting - even turn the tide in Iraq!
AVOCADO OIL!
$2,000 cash if you find a buyer for my house, kumeuhouseforsale@straightshooters.co.nz for details
Homo Sapiens Vulgaris
I'm more concerned with the terrorist applications of these weapons. They can be made with x-ray transparent materials and smuggling on aboard a plane should be possible...
It is preferential to refrain from the utilisation of grandiose verbiage in the circumstance that your intellectualisation can be expressed using comparatively simplistic lexicological entities. (...such as the word fuck.)
Remember your humanity, and forget the rest. - Joseph Rotblat
Rest In Peace
Meh who gives a hoot!!! Let's shoot some things....yyeeeaahhhhaaaa!!!
*sorry, inner redneck popping up every once in a while*
Eh Tom, make sure to post some pics of the result...please!
Hardcore Biker
thats great i was wondering how the length of the wire was going to factor into it that was my biggest problemThe simplest way of making a rough estimate would be to consider the problem from an energy conservation perspective.
The increase in potential energy of your pendulum should be equal the decrease in kinetic energy of the projectile:
dEkin + dEpot = 0
This is pretty rough since some energy will be expended deforming your projectile, localised heating, wind resistance, non-perfect wires, etc.
dEpot = (m+M)*g*dh - where m is the mass of the projectile, M the mass of the pendulum, g the gravitational constant and dh the change in height of the pendulum.
dh = l * cos(theta) - where l is the length of the wire and theta is the deflection angle.
The velocity should then be given by:
v = sqrt(2*(m+M)*g*l*cos(theta)/m)
It's important that you choose the weight of the pendulum carefully in relation to the weight of the projectile. It is also important that the entire projectile moves with pendulum. You need to establish the centre of mass of the pendulum fairly precisely - or use a very long wire.
Come warm yourself by the fire
Come one Mikkel its not like you to overlook anything.
Yes doing the parabola test has fail in it - but not due to wind resistance - due to fact that it gives you average speed.
Also shooting a avo into a bit of wood wont tell you speed if the wood spins, as the avo will deform loosing most of the energy.
If you want the best calculaiton your going to have to time between 2 points.
i.e. end of barrel to some distance that can be timed and is not too long.
If you were really cheaky you could put 2 sensors in your gun. average the speed down the barrel.
Reactor Online. Sensors Online. Weapons Online. All Systems Nominal.
L-Plate Rider
Fire it directly up, measure how long it takes to hit the ground, apply maths ?!
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