Nonsense.

Energy is required to slow a moving object. A force is required and it is exerted over a distance. Since the definition of work is force x distance then work is expended

Consider a rocket traveling to the moon (or anywhere in space) . To slow it down would require energy. We need to produce a force in the opposite direction of travel and that force is exerted over a distance. That is work done on the system.

That's interesting but you are transferring the reference frame to suit your need.
One could have a rope connected to the rocket and slow it down while turning a generator extracting energy from the moving rocket.
In space, the rocket did not know it was moving until you said it was moving from earth, so energy can be extracted now by the rope otherwise, from the frame of the rocket, firing the jets will cause acceleration and will require energy.
 
 

Jouleseeker said "
Norman, you mentioned the odd behavior of your pendulum - swung higher than the starting height?  did I get that right?

Yes you did. Norman

 Man, I'd like to try that, too, (if I got it right) --  if you could provide any pointers on how you set your magnets relative to the pendulum ball (steel, or a magnet?) to accomplish this trick.  Any info would be helpful and appreciated."

There are several tricks to the pendulum and I will enumerate but I suggest that you work on the ball and track because it has more potential.

1. metal under the flat magnets around the clock so that they can be adjusted and respaced easily because it takes lots of tweaking.. and those magnets need to be a bit away so that they will not get stuck. There is one polarity that works better so flip them to find out which one is best. I forget.
2. a slight tilt of the pendulum so that gravity is not too strong.
3. the axle/axis is coat hanger wire sharply pointed and sitting in a centerpunched dimple so that there is almost no friction.
4. a small wooden block on that axle with a metal strip to hold the magnet and since it is off center I used a white paper pointer to show where its gravity center really is when it hangs straight down or else it is visually deceptive.
5. the metal strip has a curved bend toward the drop direction and where that curve starts is a small button neo mounted 90 degrees from the flat magnets around the clock.
6. and some times I doubled up on the higher magnets and played with the spacing so there is no sticky spot.

then I made a stop at 2 oclock and when testing used a stick or something to release it
so I didn't accidently add finger power and deceive myself.

It is very easy to construct ( not more than an hr)  but it will take a lot of patience. I usually work on it for awhile and then walk away and usually when I come back things click better.
You have the advantage of a video showing what it can do. I did not have anything to go on.

Good luck, it will defy current scientific principles because we have all been taught that pendulums cannot go past the level of the dropped point but this one does. So scratch your head and ask where does the force/work come from to make it go higher than its dropped point? That discussion will probably take 20 years.

If you make it and it does not perform then I will make a closeup of the pendulum details so you can better see it but without a photo you might get it to work better than I did if you tinker enough.

Norman

Which post, Norman, gives details of your setup. Your work looks interesting and I would like to have a go.

Paul-R

the video is here but I recommend elecar's because it has more potential.

http://www.youtube.com/watch?v=4FzK2XKQ-74

Norman

 LigreEnergia - go to the bench and do something and rest your keyboard.Then come back and tell us what you learned.  That is what I did.



Norman

I think that it's a challenge to understand and talk in terms of magnetic potential energy for some people.  Gravitational potential energy is more intuitive.

Imagine a very simple setup, a straight track with two aluminum rails.  A few inches away from the track there is a magnet.

             M

A===========B

So you release the ball at point A, it's attracted to the magnet and speeds up and then stops at point B.

This is the type of effect that you are playing with when you put magnets around your closed-loop tracks and place the metal ball at a certain starting point.

It may seem that you got energy from the magnet and the ball moved from point A to point B for "free."

However, the truth of the matter is that in a way nothing happened.  The ball moved down the track but no energy was gained and likewise no energy was lost.  When you release the ball and it starts moving, the energy in the system does not change at all.  We are ignoring friction.

Can any of you track builders explain that?  You need to be able to explain that and fully understand it to work more effectively with your setups.  You should become comfortable in discussing magnetic potential energy and use that terminology in your discussions.

Hi Vineet,
                That is basically the same design used in a conventional SMOT. To my knowledge no one has ever looped one, not even one time.
I did see a design that I thought had potential that worked in a similar way, I will see if I can find the videos and post the links.

Some progress today. Increased the magnet stack and tweaked and tweaked and tweaked and got the ball to go 1/2 inch past its dropped point and then drop back down  and away from the sticky spot. The ball weighs 64 grams so this is quite a bit of extra work over and beyond my small pendulum weight of about 10 grams.

Without the magnet stack the ball would normally go about 2 inches less.
Its quite easy to do so go try it.

I worked on the escape but have nothing impressive to report.
good luck with yours.

Norman