Law of conversation of energy wrong???????

[Lakshya]

a problem.....pls check..
imagine theres a horizontal planeA bove which the effects of gravity are not felt. any object above the plane just floats and gravity has no influence on it.
now take a chain(for e.g:made of small steel ring) of length hundred metres above the planeA and arrange it so that its in a heap just above the planeA. but take care the chain is not entangled and should be easy to stretch along its length.

now pull the lower end of the thread below the planeA and the chain runs down like a single thread and hits the ground and as links pull down on the ones they are linked to , the whole length of the chain will run like a thread and hit the ground in some time. now take planeA is 20metres above the ground surface. the terminal velocity of links when they hit ground will be around 14 metres .
now consider hundred metres of the chain weighs 100 units. the potential energy of the chain just above the planeA will be m*g*h =100 *9.8*20
=19600 units.

but kinetic energy recovered would be 1/2 * m * v*v = 0.5 * 100* 14 *14 = 9800 units. so in this method only half the energy is recovered hence violating the law of conservation of energy.

SIMPLY PUT, THERES DIFFERANCE IN ENERGY RECOVERED WHEN U TAKE 100 METRES OF CHAIN TO HEIGHT OF 10 METRES AND DROP IT AS WHOLE TOGETHER THAN WHEN YOU ARRANGE IT SO THAT IT RUNS DOWN LIKE A THREAD , EACH LINK PULLING DOWN ON THE OTHER LINK IT IS CONNECTED TO...


now what will the terminal velocity be when the planeA is above 40 metres...?
i guess its around 19.6m/s instead of 28m/s......

ur thoughts pls correct me if im wrong...

[Lakshya]

Is anybody going to post on this thread.

[dleviwing]

Sorry but you cannot alter the function of gravity to suit your own thinking. You are also applying the concept of “terminal velocity” incorrectly. Nice try for someone your age though Jake.

[Lakshya]

Sorry but you cannot alter the function of gravity to suit your own thinking. You are also applying the concept of “terminal velocity” incorrectly. Nice try for someone your age though Jake.

Dleviwing, I also posted it to Milo Wolff and he showed me a flaw in it. Actually there was no problem with gravity but it was with terminal velocity. But after calculating the terminal velocity right, it still doesn't fit in. It is calculated by (2gh)^1/2 = 19.79 and then we calculate potential energy = 19600 units and kinetic energy = 19582. Now you can't say anything. Actually, I also posted on many other forums like physicsforums.com, scienceforums.com etc. and they are also debating on the concept of gravity and majority of the people say that it will have no effect.

[MJA]

Dear Laksha,

In trying to visualize the chain and the plain I found this to help.

Do your equations apply equally with a rope?

I hope you don't mind the fun.


pdcomedy.com: Road To Bali, Indian Rope Trick - Public Domain

=
MJA

[Lakshya]

Dear Laksha,

In trying to visualize the chain and the plain I found this to help.

Do your equations apply equally with a rope?

I hope you don't mind the fun.


pdcomedy.com: Road To Bali, Indian Rope Trick - Public Domain

=
MJA

Yes they also work with a rope. Actually the difference is of 18 units. Iknow that the differencxe is small but it's not negligible.