Posted by Rob (208.17.229.230) on March 14, 2002 at 15:28:30:
In Reply to: Thoughts... posted by Scott Ellis on March 14, 2002 at 00:50:32:
I find it interesting that you just described the springy pendulum.
I was looking at websites for pendulums and came across the "pendulum lab" http://monet.physik.unibas.ch/~elmer/pendulum/ that has a demo of the spring pendulum
When I tried releasing it from different positions, low and behold it went above its pivot point!
: There are many dynamic physical principles that can cause unusual effects in mechanical systems. If Bessler was genuine, he probably exploited one of these principles. One obvious example is the gyroscopic
: effects, where the apparent weight of a mass is offset from it's gravitational center if the mass is allowed to precess as it spins.
:
: I would like to describe 2 other cases where I think an
: unusual but natural, dynamic principle will cause actual results to differ
: from the intuitive expectation.
: Regardless of their merit, I hope you will keep these ideas in confidence,
: and I hope you will provide me with feedback about them.
: The two ideas are:
:
: 1. The net vertical distance gained in the resonant
: case of the oscillating spring pendulum
:
: 2. The impact vs. impulse nature of collisions of solid
: bodies
:
:
: I will describe each idea in detail:
: 1. Parametric Excitation of Oscillation in the Spring Pendulum
: We all know the rule: Rolling a ball in a bowl, swinging a pendulum,
: you can never get higher than you started. And due to friction, you
: can't even break even.
: But in truth, we can raise a weight by a certain vertical distance X,
: release it, then catch it at a height of 3X or more!
: A metal ball hangs on a spring, which is fixed in turn by one end to
: a board. If we pull the ball down and release it, the pendulum will oscillate
: in the vertical direction and then it gradually begins to swing from side
: to side similarly to a regular pendulum. After a while the horizontal oscillation
: will cease and vertical oscillation will arise again. The system will behave
: the same way if the ball is deviated aside and released. In the resonant
: case, the transfer of energy from the horizontal oscillations to the vertical
: oscillations is maximized.
: The key to maximizing the resonance is this formula:
: mg 1
:
: -- = -
:
: kl 4
: http://www.maths.tcd.ie/~plynch/SwingingSpring/System.html
: Now check out this link:
: http://www.maths.tcd.ie/~plynch/SwingingSpring/swingingspring.html
: The applet shows how a resonant swinging spring transfers energy from
: horizontal oscillations to vertical oscillations. What occurred to
: me is this: When analyzing the spring-weight system, every point on the
: path represents the same energy (spring energy + kinetic energy + gravitational
: potential = CONSTANT), that is true enough. But from a reference
: point totally outside the system, placing the weight on different points
: on the path represent very different energies. In particular, the
: path seems to transform horizontal distance (which is basically free with
: low friction), into upward vertical distance (anything but free).
: The pendulum goes higher than we started:
:
: From a reference point outside the system, it looks like we can raise
: a weight by a small vertical distance (real work) and push it over a larger
: horizontal distance (basically free), and end up with the weight at a position
: that represents substantially more (potential) energy than we started with:
: 
: If the weight were actually attached to a lever arm pivoting at the
: reference point above, the two (supposedly equal) positions of the weight
: would represent substantially different energi
http://www.efm.leeds.ac.uk/CIVE/CIVE1140/section04/mechanics_sec04_full_notes02.html
:
: http://hyperphysics.phy-astr.gsu.edu/hbase/impulse.html
: There is another way to think about impulse, however, and that is as
: the 3rd derivative of position with respect to time.
: x = position
:
: x' = velocity
:
: x'' = acceleration
:
: x''' = impulse?
: In May 1962, Dr. William O. Davis published "The Fourth Law of Motion".
: In the paper Davis puts forward, rather convincingly, some strikingly persuasive
: arguments for the possible existence of a force proportional to the third
: time derivative of displacement (or position), usually known in engineering
: circles as "surge", "jerk", or "rate-of-onset."
: Below are some important extracts.
:
The class of anomalous behavior which we wish to study involves
: in every case the presence of surge as we have just defined it.
: Under conditions of constant or zero acceleration mechanical bodies or
: systems of bodies obey Newton's Laws reasonably well. It is
: under conditions of changing acceleration that difficulties arise. The
: key word in our analysis of dynamic systems will be "simultaneity".
: The Laws of Motion presuppose exact simultaneity of action and reaction......to
: satisfy Newton's image of the universe.: Newton's Laws, strictly speaking, apply only to mathematically infinitesimal
: particles or perfectly rigid bodies, neither of which exist in the real
: world.: Consider, for example, a simple steel rod one meter long which I wish
: to move by applying a force to one end. The instant I start to apply the
: force a message leaves the end of the rod as a plastic or elastic compressive
: wave which travels at a speed of approximately, 5,000 meters/second. The
: compressive wave travels to the far end of the rod where it is reflected
: as a rarefaction and returns to the point of application of force at the
: same speed.: Until the wave returns, 4/10,000 of a second later the rod as a whole
: cannot move according to the Second Law! No matter how much force is applied,
: the center of gravity of the rod cannot obey F = ma in less than this time.
: It would be oversimplifying to say that the rod acts as though it had infinite
: mass during this time, since the center of gravity will be moved somewhat
: by the compression, but for all practical purposes, the rod acts as though
: it had a much larger mass than it actually has.: ...The particular behavior of a given system will depend on: (a) how
: rapidly the force is applied and, (b) the built-in delay time, or "critical
: action time" of the system. More exactly, we have found that the behavior
: depends upon how rapidly one attempts to change the acceleration applied
: to the body. The ultimate acceleration of the body, the "a" of F = ma,
: is not what is critical; it is the rate of onset or "surge" of the acceleration
: which is vital.: ...There is no conflict here with Newton, for Newton considered only
: systems where either velocity or acceleration were constant. Since his
: data inputs were from astronomy and since he had no instruments capable
: of investigating effects of changing acceleration - effects that
: may occupy milliseconds or less - this is not particularly surprising.: ...Starting transients normally are considered only in connection with
: the beginning or the end of a motion and hence are accorded no particular
: attention. However, there are certain types of cyclic motion where
: the transient behavior is continuous, or repetitive and we will see later
: that even certain single transients may have critical importance in understanding
: natural events...[This] solution demonstrates the most significant characteristic
: of real bodies, to wit: not only is displacement somewhat less than Newton
: would predict for a given force, l
: would predict. The existence of intractance permits many more modes of
: resonance since there are now four terms in interaction in the equation
: of motion for a system including viscous damping and linear restoring force
:
: instead of three. This permits a much greater number and variety of
: resonances to occur.
An entirely new means of securing a reaction was next tested.
: The rocket was made up of a series of chambers the ends of which consisted
: of steel disks fastened together by a 1/4 inch diameter steel rod. The
: chambers were arranged to explode in series, blowing the steel disks downward
: with great velocity. Knowing the weight of the disk and its velocity and
: also the weight of the complete rocket it is a simple matter to find the
: energy of the recoil. Although this type of rocket works, it leaves much
: to be
:
: desired in the line of safety.: A series of tests now followed which I believe are original in the field
: of reaction. They dealt with a form of impact-impulse reactions which are
: created mechanically. The apparatus if placed in a box in space would move
: without the use of a jet of any sort, it being propelled by a reciprocating
: motion of two weights. The truth of the theory may be easily proven by
: a very simple apparatus.: The theory is that a large weight with a low velocity ( if stopped
: by springs ) will yield more foot pounds of energy than a small weight
: with a high velocity being stopped by impact, even though both were given
: the same initial force. A simple illustration: Let us assume you are
: in the center of a room in space. One wall is elastic and the opposite
: one solid. In your hands are two balls one heavy and the other light and
: you throw them with the same force at the same time. The heavier one hits
: the elastic wall with an impulse and a large amount of energy is given
: to the room in that direction. The lighter one having the same energy hits
: the solid wall but its energy is dissipated in heat and distortion. If
: there could be found a method whereby the kinetic energy of the lighter
: ball could be effectively utilized the room would move in the other direction.
This elementary form of reaction motor operates on a principle
: that has long been neglected by engineers, but which Bull believes can
: be applied in aircraft and other vehicles. It depends upon the difference
: in effectiveness of two ways of transmitting energy, which can be termed
: impact and impulse. If a weight is thrown against a solid wall, it is stopped
: by impact, and much of its energy is wasted in distorting the weight and
: the wall and in producing heat. However, if the weight is thrown against
: a spring fastened to the wall, it is stopped by impulse, the spring conserving
: the energy of the moving weight and transmitting the resulting force, with
: little loss, to the wall. Tests have shown a weight will yield three
: times more force by impulse than by impact.: ...Achieving a practical reaction motor, Bull points out, depends to
: a large extent, paradoxically, upon how inefficient it can be made. The
: more force that can be wasted in impact, the greater force will be left
: to push ahead, a new problem for engineers, who have spent years trying
: to conserve energy rath http://jnaudin.free.fr/html/hbimp35.htm
:
: http://www.forceborne.com/cip_principle.htm
:
:: Now, Imagine the following: A solid beam that pivots at
: its center and 2 weighted, individually hinged lever arms sticking straight
: up, also pivoting at the center. Classical physics says that if the
: two weights fall simultaneously to either side, they can't provide any
: net torque to the beam. But assume one side of the beam is designed
: for impulse and the other for impact. It the 2 arms fall and strike
: the ends at the same time, there WILL be a net rotational force applied
: to the beam.:
: -------------------------------------------------------------------------------------------------------------
:
:: I hope I have described two scenarios where natural dynamic principles
: cause peculiar effects. I look forward to hearing your feedback and
: ideas.: ???
:
: Thanks,
:
: Scott
