Hey like my math on the "Beck Mickle hydro generator"?

[Oznog]

I heard from a guy telling how great this new amateur-invented backyard hydroelectric generator is supposed to be. 2KW from 8" of head.

I had to do the math on this one, since it's all easily calculable. The numbers get pretty... implausible.
I went ahead and posted it under the PESWiki entry for posterity, titled "Performance Calculations":
https://peswiki.com/index.php/Directory:Beck_Mickle_Hydro_Ltd._Micro_Hydro_Generator

I hope I didn't make any math errors. I did try to double check it.

 

[Pommie]

I can't do Lbs Feet etc.

In metric it comes out slightly different

Joules = Mass * Height * Gravity

2000 = M * 8*0.0254 * 9.81

M = 1003Kg = 1003 Liters = 265 Gallons

Close enough.

Mike.

 

[dknguyen]

I think a slug is the most ridiculous unit to ever walk the Earth.

 

[Oznog]

The metric system is the tool of the devil!
[SIZE=-1]My car gets forty rods to the hogshead, and that's the way I likes it![/SIZE]

 

[ljcox]

The metric system is the tool of the devil!
[SIZE=-1]My car gets forty rods to the hogshead, and that's the way I likes it![/SIZE]

I gave imperial away as a bad joke 40 years ago.

12 inches in a foot, 3 feet in a yard, 22 yards in a chain, can't remember (and don't wish to) how many chains in a furlong, etc.

12 oz in a lb, 112 lb in a hundred weight, etc.

16 fluid oz ina pint, 2 pints in a quart, 4 quarts in a gallon.

What a ridiculous system!!

 

[Nigel Goodwin]

I gave imperial away as a bad joke 40 years ago.

Obviously true!.

12 oz in a lb

There's 14 oz in a lb!

 

[ljcox]

There's 14 oz in a lb!

Oh, is there? That shows how long it is since I used the stupid system.

 

[Nigel Goodwin]

You also forgot to mention:

12 pennies in a shilling
20 shillings in a pound
21 shillings in a guinea

 

[Pommie]

Obviously true!.



There's 14 oz in a lb!

Are you telling me that a quarter pounder only weighs 3½oz. No wonder I've been losing weight

Mike.

 

[Nigel Goodwin]

Are you telling me that a quarter pounder only weighs 3½oz. No wonder I've been losing weight

Actually, I was wrong as well!.

There's 16 oz in a lb
and 14 lb in a stone
(probably!)

 

[ljcox]

Actually, I was wrong as well!.

There's 16 oz in a lb
and 14 lb in a stone
(probably!)

Yes, you're right. I'd fotgotten about stones.

Also the British ton is 2240 lb but the Amercian ton is 2000 lb!!!

 

[Oznog]

An ounce of feathers is lighter than an ounce of gold.
However, a pound of feathers is heavier than a pound of gold.

The first statement is odd enough- the second being contradictory is just absurd.
Yet both are completely true.

 

[ljcox]

An ounce of feathers is lighter than an ounce of gold.
However, a pound of feathers is heavier than a pound of gold.

The first statement is odd enough- the second being contradictory is just absurd.
Yet both are completely true.

Of course they are not true.

The weight is the same in both cases.

However, it may be more difficult to lift a pound of feathers as they will fill a larger volume thus making them feel heavier.

 

[Nigel Goodwin]

Of course they are not true.

The weight is the same in both cases.

I feel you're missing the point! - gold is weighed in 'troy ounces', not normal ounces - and they are different. Don't know if 'troy pounds' exist or not, it's not something you really measure gold in!

BTW, the use of 'feathers' was a trap you fell into, he could just as easily said 'lead'.

 

[ljcox]

I feel you're missing the point! - gold is weighed in 'troy ounces', not normal ounces - and they are different. Don't know if 'troy pounds' exist or not, it's not something you really measure gold in! .

Yes, I had forgotten about troy weight. But I feel it proves the point I was making about it being a ridiculous system.

BTW, the use of 'feathers' was a trap you fell into, he could just as easily said 'lead'.

No, if you re-read what I wrote, I said it may be more difficult to lift due to the volume (not the weight), ie. it would be a larger container that would be more awkward to lift.

 

[Sceadwian]

1 ounce is .911 troy ounces, not exactly a huge difference.

 

[Oznog]

I feel you're missing the point! - gold is weighed in 'troy ounces', not normal ounces - and they are different. Don't know if 'troy pounds' exist or not, it's not something you really measure gold in!

BTW, the use of 'feathers' was a trap you fell into, he could just as easily said 'lead'.

Yep. Now the thing is, there IS a troy pound and that would be the correct pound to state gold weight in. However, there are only 12 troy oz in a troy pound, whereas there are 16 avoirdupois oz in an avoirdupois pound. Thus, even though an oz of gold is heavier than an oz of feathers, a pound of gold is lighter than a pound of feathers.

Other interesting units, a "gallon" can be US liquid, US dry (rare), or an Imperial gallon (UK). UK vehicles get 20% better mpg because their gallons are 20% larger. Great way to save gas, eh? We should start using their Imperial gallons to help show those oil companies who's boss.

 

[ljcox]

Yep. Now the thing is, there IS a troy pound and that would be the correct pound to state gold weight in. However, there are only 12 troy oz in a troy pound, whereas there are 16 avoirdupois oz in an avoirdupois pound. Thus, even though an oz of gold is heavier than an oz of feathers, a pound of gold is lighter than a pound of feathers.

Other interesting units, a "gallon" can be US liquid, US dry (rare), or an Imperial gallon (UK). UK vehicles get 20% better mpg because their gallons are 20% larger. Great way to save gas, eh? We should start using their Imperial gallons to help show those oil companies who's boss.

I rest my case.

 

[Sceadwian]

We should all just switch over to the metric system, these unit differences are absurd. I used to think I'd always be in the American frame of mind, our system after all makes sense to us. Until a few years ago when Nasa screwed up and made a unit conversion mistake which killed a mission. Ever since then I've jumped on the give it all up and go metric bandwagon. The whole 1/16th of an inch thing always ticked me off. mili micro nano pico femto that's all I want to remember. Besides the ones a little further down atto zepto and yocto just sound neat =>
The difference in kgs and lbs and meters and feet are taking me a little while to get used to mentally but I plan on having it all sorted out before I'm in my 30's =)

 

[ljcox]

Yes, in 1964 I became so fed up with measuring in 1/8ths, 1/16ths, etc. that I ordered a metric rule from the hardware shop and have not used imperial since.

One of the best decisions our government made was to convert to metric in the 1970's.

No-one ever refers to temperature in degrees F now, most measure their weight in kg but many, including the young still refer to people's height in feet.

It is just a matter of accepting the advantages of metric (and the hopelessness of imperial) and becoming familiar with metric.

It also pays to remember that Volts, Amps, Watts, Ohms, coulomb, etc. are metric units and fortunately, no-one was silly enough to invent imperial versions.