Posted by Øystein Rustad (217.70.229.49) on August 18, 2002 at 03:34:59:
In Reply to: Re: Strings and weights within a wheel (and many other interesting things!) posted by Scott Ellis on August 17, 2002 at 10:49:10:
Hello, I just want to make some correction about the java applet !
There are to many errors in this applet to prove anything.
This Tony guy also seems to be confused about how a PM wheel should work if it worked.
And he have also drawn the function of the wheel wrong.
If you put in smaller string lenght you will see what I mean.
If we should follow physics reasoning, the applet or the conclusion of the author fails, and show us PM. Because :
Torque is a way to generate potential energy !
Torque "must" be propotional to potential energy, or else a PM would be possible.
The volume of a positive torque curve MUST be equal to the volume of the negative torque curve, or else we also have PM.
Take a look at the torque curve....
The question is : What volume of a torque curve do you need to gain wanted potential energy..?
And what volume of torque curve do you get when the potential energy is released ?
First :
The resault is that potential energy calculation is a waste of time !!
Next : How do we determine the volume of the positive and negative torque curve ??
The most secure way is to add up all possible points of equally spaced torque measurements... The applet do measure for every 0,01 degree and should contain that info. but does not reveal it.
BUT if we take a look at the torque curve we get, we have a feeling that the negative torque curve is smaller in volume than the positive.
Actually the positive torque curve is 38% longer than the negative torque curve.
The author say that because the negative peak is 0,003% more negative than the positive peak the wheel will run backwards and position itself there...
That is true, BUT from the torque curve, the wheel would never stop, and come to this, because of what is called momentum / kinetic energy.. gained from slightly more positive torque
(if the applet is correct)
To see that the length of the torque curve is as important as the top/max value we can analyze a right angeled triangle...
Volume : lenght * height / 2 !!!!
Then we see that the applet shows :
Torque max at 4,66 degrees and + 0,304
Torque min at 5,64 degrees and - 0,305
Volume of positive triangle :
4,66 * 0,304 / 2 = 0,708
Volume of negative triangle :
9 - 5,64 = 3,36 * - 0,305 / 2 = 0,5124
This gives us 38% more positive than negative torque ....very
roughly..... how come ?
2 alternatives :
Either the applet is wrong, and the author don`t understand perpetual motion, or the Marquise of Worcesters wheel did work as claimed !
With 40 heavy weights ina BIG wheel giving the momentum needed to transfer to positive torque over the smaller negative ereas and never ending up as the author suggests....
Øystein
: Hello All,
: Thanks for your post, Joel. However, my discussion board program limits the size of a post to 100,000 characters. This is to prevent a malicious person from posting a message so large that it fills up my hard drive.
: Anyway, the verbage that Joel posted comes from a book entitled "The Century of Inventions" by Edward Somerset, Marquis of Worcester (with commentary by Henry Dircks). The entire book is available online, together with many of the drawings and diagrams. The specific page from which Joel copied his verbage, which addresses the Marquis' overbalanced wheel is here:
: http://www.history.rochester.edu/steam/dircks/His111chap1.html
: And this link will take you directly to the section about the overbalaced wheel, the section titled "An advantageous change of Centres":
: http://www.history.rochester.edu/steam/dircks/His111chap1.html#454
: Though the Marquis' overbalanced wheel is interesting, and indeed seems like it might work, the wheel actually balances. In fact, here is a websi