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Help With Power Calculation Please

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bill barlow | 18:26 Mon 20th Jan 2014 | Science
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I have designed and built a device that harnesses centrifugal force.The power output is in the form of
2 x 10mm steel rod "pistons" that move up and down a distance of 15mm. I have measured the weight these pistons can lift to be 122lbs when the device is operated @ 4000rpm. Each piston moves up and down once per revolution. I have calculated this to be an output of 1.45 hp. ( 15mm=.049125ft x 66.666 times per second=3.27496 ft x 122lbs = 399.54 lbs/ft/sec = .7264hp x 2 = 1.45hp. Can people please either confirm my calculations are correct or point out my error(s).

If I am correct,given that the device is solely powered by a 500w electric drill, am I able to claim the impossible?
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How did you measure the weight they can lift?
bill, you need not worry about the calculations until it can be shown to work.
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nescio thank you for your contribution. I do not understand your second paragraph though.
Can we forget what drives the device and answer my original question re power output and my calculations please? Thank you.
I would like to if you can tell me how you measured the weight?
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Tora, I put the weights on the piston. The weights totalled 122lbs and the piston lifted them 15mm 66.66 times per second. But why does it matter?
A portion of the inertia of reciprocating piston mass is recaptured by the crankshaft during piston deceleration phases. This diminishes the apparent work done in moving the piston back and forth.
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Thank you mibn2. Did you go to a special school?
I'm currently studying for an associates degree in web browsing at Google U ;o)
I never thought I'd encounter in the 21st century a crank who thinks he has invented perpetual motion. I find it fascinating.
"why does it matter"! - the fact that you ask that tells me all I need to know! Forget any calculations, forget any comments above, test the theory. Connect your "engine" to a small alternator, it can turn that can't it? Feed that to a car battery, connect a 12v-240 transformer to the battery and plug the drill into that. Also plug the drill into the mains, split the wires so both sources feed the drill. Turn on the mains and the drill, leave the drill on and turn off the mains. If you are correct the "engine" should run fior ever with no power input. Tada, nobel prize!
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tora. I,d prefer you you tell me why it matters please? And answer my initial question?
@bill

//I have measured the weight these pistons can lift to be 122lbs//

You said 'lift' and 'weight'.

For starters, weight is a force. Mass x gravity

50kg x 9.81 = 490 N

Force x distance (meters)

15mm = 1.5 cm
1.5 cm = 0.015 m

490 x 0.015 = 7.35 Nm

66.666 times per second = 489.9951 NM.s^-1

500W in, 490W out.

98% efficiency is pretty impressive. Nice set of bearings you're using!




490 x 0.015
p.s. the way you wrote it implies that it took both cylinders to lift the 122lbs, therefore there is no multiplying by two to do.

nescio thank you
but moving 1 kg at right angles to gravity I metre - is 50J ?
innit. or is it zero ?

no -one joule - sorry past midnight.
I presume that's a joke, Tora. There are any number of ideas like yours, all of which have fallen flat because they have not allowed for losses.

I was talking in the pub to someone who simply couldn't understand why you couldn't connect a motor to an alternator to feed the motor.

Give it up, Tora. It ain't possible.
why are you telling me to give it up, it's not my post, I know the FLOTD.
http://en.wikipedia.org/wiki/First_law_of_thermodynamics
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thank you hypognosis
I find it amusing that people without clue about physics expect to be able to design anything.

There is no power output at all.
//There is no power output at all.//

I wouldn't go so far as to say that beso. With the proper adaptor I can see how such a device might function quite admirably and effectively as a vibrator.

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