| Author | Message | |||
     Anonymous |
could a large circular Magnetic Linear Accelerator be a perpetual motion machine ? | |||
| Simon Quellen Field (sfield) New member Username: sfield Post Number: 210 Registered: 12-2004 |
No. This is covered pretty completely in the last section of the Gauss Rifle page. | |||
| got it Unregistered guest |
Ya I did get another idea though. think if you had a track that looked like this.  it would never run out of balls because of the circle on each side. the direction of the ball entering the circle would always change with some thing like in the drawing it will pivot because when the first ball leaves it will turn it so the next ball will enter in another way | |||
| Simon Quellen Field (sfield) New member Username: sfield Post Number: 212 Registered: 12-2004 |
So who is pulling the balls off the magnets and stacking them on the other side? Remember, the state of the balls and magnets are different after a ball hits the magnet. Who does the work to reset the state? | |||
| lysdexia Unregistered guest |
got it, how old are you? | |||
| Larry G. Lowe (Unregistered Guest) Unregistered guest Posted From: 70.245.131.22 |
Hey, yo! Check out this pic. This is a design I came up with like several years ago. It uses a "rail-car" with two wheels on top, and two wheels on bottom. Moving to the left, the wheels on top spin clockwise. Moving to the left, the bottom wheels spin counter-clockwise. The car actually rests on the tracks above and below it, on it's axles. There are four axles, two on top, two on bottom. The wheels attached to those axles do not touch the tracks, they act as "flywheels". This helps when the rail-car gets to the up hill turn. Basics: The downhill turn on the left of the picture is exactly half as high as the uphill turn on the right. The drawing shows the device sitting upright as it should. The rail-car goes downhill in a straight line, drops downhill on the left hand turn, then goes downhill in a stragiht line to the right, this allows momentum to build, and allows the "flywheels" to get spinning very fast, so as to force the rail-car uphill the turn that is bigger than the downhill turn. The overall length of the entire wall mounted toy is approximately six feet. This equates to 6 foot of downhill slope to the left, 1/2 foot of downhill turn, 6 foot of downhill slope to the right (this is the acceleration section of the track). Then 1 foot of uphill turn (this is deceleration section of track). Hope you enjoy. This one runs until the bearings attached to the axles wear out. Peace.
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| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 769 Registered: 12-2004 |
What makes you think that falling down can give you enough energy to climb back up? That's like saying a car on the downhill side of a circular track will pick up enough energy to coast back up the other side, or that a pendulum picks up enough speed on the down stroke to come all the way up to the same height on the return. If you actually build your device, you will see what I mean. | |||
| Eugene, S (Unregistered Guest) Unregistered guest Posted From: 154.20.115.178 |
Simon, I cannot find your Gauss Rifle page. I want to look this up. | |||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1008 Registered: 12-2004 |
It's the fifth link on the main page. | |||
| Eugene, S (Unregistered Guest) Unregistered guest Posted From: 154.20.115.178 |
Simon, am I correct in assuming that ball #2 is just a spacer to keep ball #3 away from the magnet, and that it could be made of any hard elastic material, the lighter the better. Also that the ball(s) to magnet weight ratio makes a difference for resultant power of the gun. I did order your gauss rifle kit. I intend to optimize it for maximum power. Any suggestions? | |||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1023 Registered: 12-2004 |
No and no. The balls and the magnets should be matched in mass. All of the balls. Having different masses creates an impedance mismatch, resulting in reflected energy that is not delivered to the target, and is instead wasted as heat in the gun. Picture a BB gun aimed at a cannonball. The BB simply bounces off, and the cannonball does not move. If a cannonball rolled into a BB, all of the work you did to get the cannonball rolling would only result in the cannonball and the BB rolling in the same direction at the same speed. If the masses are matched, like in billiards, the cue ball will stop and the eight ball will get all of the energy. | |||
| Eugene (Unregistered Guest) Unregistered guest Posted From: 154.20.115.178 |
Quoting from your description: "the speed does not add up linearly. If we have 4 magnets, the kinetic energy is 4, but the speed goes up as the square root of the kinetic energy. As we add more magnets, the speed goes up by a smaller amount each time. But the distance the ball will roll, and the damage it causes to what it hits, is a function of the kinetic energy, and thus a function of how many magnets we use." Does this mean that shooting straight up, and assuming that one magnet sends the ball up one foot, then two magnets will send it up four feet and four of them to 16 feet, and if the fifth one does not shatter that will send the ball to 25 feet? One more Q: You say using too many magnets will shatter the last one. How many is too many? Eugene | |||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1062 Registered: 12-2004 |
No. Speed is not height. If one magnet can lift a ball two inches, then two magnets, placed two inches away from one another in the rifle, will lift a ball four inches. Gravity adds up the same way the magnets do. You will just barely be able to lift a ball to the top of the rifle. | |||
| Eugene (Unregistered Guest) Unregistered guest Posted From: 154.20.115.178 |
Of course! Silly of me. I'm forgetting my formulas in my dotage. I'm getting about ten inches from one magnet, and about twice as much with two straight up. Eugene | |||
| Barbra Krueger (Unregistered Guest) Unregistered guest Posted From: 69.208.121.237 |
INCONSISTENT RESULTS My son and I made a Gauss Rifle. We wanted to know how magnet spacing effected the force of the last ball. We measured for length (how far the ball rolled off the end of the board) and strength (how heavy an object could be moved). I expected that the closer together the magnets were the more force there would be (so it would go farther and move heavier objects). We placed the magnets 4, 5 , and 6 inches apart and measured carefully. But our results were a little inconsistant. Shouldn't the end force consistantly increase the closer together the magnets are? PS Your kit was fabulous! We originally tried to make one on our own, but your magnets were MUCH more effective. | |||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1088 Registered: 12-2004 |
You might experiment with spacing the magnets at increasing distances. For example, 2 inches, 4 inches, 8 inches, or 2, 4, 16, or 1.5, 2.25, 5.0625, etc. When results are inconsistent between runs with the same setup, the problems are usually caused by not controlling all of the independent variables, such as where the initial ball is released, how the magnets may have moved during reloading, the angles of the magnets, or having all the north poles going in the same direction. When results are inconsistent with initial assumptions, the problem is usually due to the initial assumptions. ;-) | |||
| Eugene (Unregistered Guest) Unregistered guest Posted From: 154.20.115.178 |
I assumed that increasing the distance between magnets would increase the speed, since the ball accelerates between the magnets. Reason: the more time allotted for acceleration the more power and speed generated. However, I got inconsistent results too. Another reason for inconsistent readings (other than the ones Simon mentions) is the surface quality of where magnet and ball touch. both must be smooth and clean. Notice that the Nickel plating is peeling from some of the balls, this debris or other junk the magnet sucks in, might get in the way of good energy transfer. This is what happens as the ball rolls towards the magnet: Phase 1 (more than 2 inches): the ball is rolling towards the magnet but it's too far from it to feel the magnetic attraction, and the usual losses (friction, etc) will decelerate the ball. Phase 2 (2-1 inch): the magnetic attraction is about equal to usual losses, the ball is rolling at a steady pace. Phase 3 (less than 1 inch): the magnetic force overrides every other influence and accelerates the ball forcefully. My conclusions: Long distances between magnets will be detrimental because the initial speed of the ball will slow down before the magnet takes over. Medium distances variations would make very little difference to the outcome. Very short distances (1/8 inch) would shorten acceleration time and thus final speed would suffer. On level rails, I think, 1 inch between ball #3 and magnet probably yields the best result. Eugene | |||
| Simon Quellen Field (Sfield) Senior Member Username: Sfield Post Number: 1090 Registered: 12-2004 |
Some other things to consider: 1. At close distances, the ball is not rolling. It is sliding on the rails. 2. At longer distances, some of the energy is going into making the ball spin. 3. A spinning (rolling) ball hitting a magnet will not transfer the energy in the spin to the next ball. That energy will be lost as heat. 4. The faster the ball moves, the more friction losses there are, and the effect is not linear. And so far no one who is talking about "inconsistent" results has said what they mean by the word. Inconsistent from run to run (experimental error and noise) or inconsistent with their preconceived expectations? | |||
| Eugene (Unregistered Guest) Unregistered guest Posted From: 154.20.115.178 |
Well, I meant inconsistent from run to run, and I think, that's what Barbra meant too. Eugene | |||
| Wii552 (Unregistered Guest) Unregistered guest Posted From: 216.183.151.112 |
If i built a Guass Rifle that had a billion magnets in it, and when i used it none of the magnets shattered, how much energy would the ball that was shot have? | |||
| Theresa Simmons (Theresa) Advanced Member Username: Theresa Post Number: 70 Registered: 1-2008 Posted From: 66.160.174.128 |
Look at the 12th post on this page: "http://scitoys.com/board/messages/9/437.html". You can continue that table until you reach 1 billion magnets. Of course the gun would be 32 miles long, and take 32 years to load. The table shows how to make the speed double with each row. Continuing that to the tenth row, you would have over a million magnets, and the ball would exceed 5,236 mph. By the 15th row, you would have 1,073,741,824 magnets (a little over a billion) and the ball would be travelling at 167,563 mph. On the 20th row, you would have over a trillion magnets, and the ball would be travelling in excess of 536,127 mph (0.00799 times the speed of light). Put another way, the 12th row, with 16,777,216 magnets, would almost reach earth's escape velocity. To get the energy, you multiply the mass of the ball times the square of the velocity. All of this ignores the extra friction, any relativistic effects, and the practical engineering problems involved in such a project. How soon will you have the $4 billion dollars you need for the magnets? |
Gravity Power