Using flywheels to increase FE

[jamesqf]

No, capacitors discharge as 1/e^t, so after one time constant t, about 63% of the charge flows, in the second time constant 63% of the remainder, and so on out to infinity. Check any basic physics or electronics reference, for instance here: http://www.kpsec.freeuk.com/capacit.htm

[Xringer]

So, if I had a 10,000 farad capacitor charged up to 9 Volts and I connected a 9 ohm resistor across it, I wouldn't get 1 Amp of current flow when I flipped the switch?
Of course the voltage would drop over time..



That's why I said "A Capacitor works almost exactly like rechargeable battery."

If someone could come up with a cheap 10,000 farad capacitor the size of
a AAA cell, then all our battery problems would be over..
It would be the ultimate rechargeable battery/cap..

[Nden]

this post reminds me of a new motor i saw on BEYOND TOMORROW (discovery channel). in fact i believe it was in the new recently..few months ago. an australian inventor has built a motor that runs on compressed air. sorry but that's all i recall about it unless i find more 411

[SuperTrooper]

Originally Posted by Nden

this post reminds me of a new motor i saw on BEYOND TOMORROW (discovery channel). in fact i believe it was in the new recently..few months ago. an australian inventor has built a motor that runs on compressed air. sorry but that's all i recall about it unless i find more 411

Here's the thread:

http://ecomodder.com/forum/showthrea...09-a-1143.html

[jamesqf]

Originally Posted by Xringer

So, if I had a 10,000 farad capacitor charged up to 9 Volts and I connected a 9 ohm resistor across it, I wouldn't get 1 Amp of current flow when I flipped the switch?

No. If you look at instantaneous current flow, it will follow the same exponential decay curve as that voltage plot. You'd have a current flow of many amps for the first fraction of a second, declining to a fraction of an amp after several seconds. A battery would supply nearly constant current/voltage until it's depleted.

[ttoyoda]

Quote:
Originally Posted by Xringer View Post
So, if I had a 10,000 farad capacitor charged up to 9 Volts and I connected a 9 ohm resistor across it, I wouldn't get 1 Amp of current flow when I flipped the switch?


No. If you look at instantaneous current flow, it will follow the same exponential decay curve as that voltage plot. You'd have a current flow of many amps for the first fraction of a second, declining to a fraction of an amp after several seconds. A battery would supply nearly constant current/voltage until it's depleted.

jamesqf,
I believe you may be mistaken.
From V=I*R we get I=V/R. Putting in 9 for the volts (V) and 9 for the ohms (R) we get 1 amp (I). Now as the current flows, the voltage in the capacitor drops, so the current gets lower with time, perhaps along the lines of a time constant RC. But the maximum current at the start when the switch is first closed is 1 amp.

[Xringer]

Originally Posted by jamesqf

No. If you look at instantaneous current flow, it will follow the same exponential decay curve as that voltage plot. You'd have a current flow of many amps for the first fraction of a second, declining to a fraction of an amp after several seconds. A battery would supply nearly constant current/voltage until it's depleted.

If by "many amps", you mean 1 amp, then you are right. The usec the switch
is closed, there will be 1 amp of current flow I=E/R (9 Watts of heat will come out of the resistor) and then over time, the voltage (and current) will drop off. And the heat will drop off slowly too.

To get a lot of amps flowing from the 10,000 farad capacitor, you could just
short it out with a heavy jumper wire. But, I would avoid being in the area,
since that 9 volts and some really high amperage just might vaporize any undersized jumper.

When I worked for NEC, we had 1.0 Farad 5V capacitors on some of the test gear. The caps were installed to preserve the data in the memory chips, in case of power failure.. They were used because the designer didn't want to use a Nicad battery. They worked very well. We never lost any data.

[merccom]

i realize i'm way late on this but the idea of a flywheel is basically as an inertia drive. induce spin, as its spinning it holds onto the energy as inertia. when you pulse and glide your basically doing the same thing.

as you speed up you gain momentum, when you take the car out of gear and just let it roll you are useing up the cars stored momentum/inertia

[theunchosen]

I hate to be the bearer of bad news. . .

If you have a huge flywheel(or even a small flywheel spinning very fast) and you turn or tilt itin any fashion its going to go haywire. . .There is a video of some people playing a trick on a bus boy(back in the 30s or 40s) where a large low friction flywheel is inserted in a suitcase. The wheel is accelerated to high speed and then handed to the unsuspecting carrier. When he rounds the corner it yanks the suitcase out of his hand and jumps straight up and into the wall.

If you change the direction of the wheel an equivalent amount of force(however much energy is in the wheel) will be applied 90 degrees opposite and out of plane (read cross product) from the original turn. So if you turn left the trailer tries to climb up, right it digs into the pavement and tilting it causes it to swerve sideways.

If you were going to go completely straight(no tilting or twisting of ay kind) then it would work fine.

[MazdaMatt]

That's a hilarious prank... please find the video

I was under the impression that F1 was going to go to a flywheel hybrid design... maybe it was just smoke in the breeze, but its a novel concept...