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Posted
Anybody know how to work ot the BHP from Nm & RPM ???

Power (Watts) = Torque (nm) x angular velocity (Radians/sec)

Radians/sec = 2 x pi rpm/60

1hp = 750.4 Watts

Well done, but one hp is defined as 550 ft lb / s  * g

(where g is the gravitational constant)

which equals 745.7 W

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Posted
Interesting article here

Interesting article but misleading almost to the point of being completely wrong. It's  a barstool explaination at its worst!  :bangshead:

In what way do you consider it misleading?  The guy who wrote it has even been applauded by the SAE for producing an accurate, simple, description of the subject matter.

Posted

In what way do you consider it misleading?  

that would be the energy comment here:

"If you have a one pound weight bolted to the floor, and try to lift it with one pound of force (or 10, or 50 pounds), you will have applied force and exerted energy, but no work will have been done."

Exerted energy? by applying a force to something that doesn't move?

A he[insert double toothpicks here] of a lot of energy is exerted by all the things resting on the floor then. Table, chair, house, Big Ben, London, the humber bridge, England for instance....

The rest is actually very well explaining things except that it could do with some SI units!

Posted
which equals 745.7 W

Curiosity demanded re-checking my tables - just a typo! well spotted - knew as soon as I wrote this it would be scrutinised.

Posted

www.speed-buster.co.uk/]www.speed-buster.co.uk[/url]

i was the north east agent for them when i was fitting them. they are a very good quality box. i never had a faulty box all the time i was fitting them..

figures are a touch optimistic, but they are good value for money/ plus when you are done the box comes off and sells for decent money 2nd hand!

on that note!!!!!!!!!

got a 2nd hand one here only done 2,000 miles off my old 330d sport, will fit all the 3.0 diesel  184 bhp 5 0r 3 series and early x5. if anyone wants one??? before i put it on ebay... :0  ???

Posted
westyzx12 - you d be the man i met at croft a week or so back. i was admiring your colour sceme in the pit lane.
Posted

westyzx12 - you d be the man i met at croft a week or so back. i was admiring your colour sceme in the pit lane.

yeh you the lad i was talking to when i was waiting to go on track ???

have just waved goodbye to the green westy , lad just picked it up   :down:  :down:  :down:  its now on route to  its new home near Liverpool.. it may well be "spotted" heading away down the M6 tonight  :0  :0

Posted
In what way do you consider it misleading?  

that would be the energy comment here:

"If you have a one pound weight bolted to the floor, and try to lift it with one pound of force (or 10, or 50 pounds), you will have applied force and exerted energy, but no work will have been done."

Exerted energy? by applying a force to something that doesn't move?

OK, I'll bolt a 10lb weight to the floor, you try to lift it with a force of whatever you want, and after you've been doing that for 30 minutes tell me you haven't exerted any energy!

Posted

OK, I'll bolt a 10lb weight to the floor, you try to lift it with a force of whatever you want, and after you've been doing that for 30 minutes tell me you haven't exerted any energy!

now, if you hadn't bolted it to the floor we would have exerted energy liting it, it's those bolts that stop us exerting energy!  :D

Hadn't realised it was ur website when was a little critical of the article u included, had a good read again, I admit it quite good really, just the Kronenbourg amplifying a few flaws last nite!

Posted

OK, I'll bolt a 10lb weight to the floor, you try to lift it with a force of whatever you want, and after you've been doing that for 30 minutes tell me you haven't exerted any energy!

The fact that your muscles require energy to produce a force is not relevant here, if I attach a big helium balloon on it, it is not exerting energy.

Just a quick query: would you know what I was talking about when I would say: "spherical horse in vacuum ? mhwa.gif"

Posted
The fact that your muscles require energy to produce a force is not relevant here, if I attach a big helium balloon on it, it is not exerting energy.

It is relevant because that is exactly the situation he is describing.  He is not talking about a helium baloon which, as you say, is not expending energy....

Posted
Just a quick query: would you know what I was talking about when I would say: "spherical horse in vacuum ? mhwa.gif"

Go on then.......

Posted

If you have a one pound weight bolted to the floor, and try to lift it with one pound of force (or 10, or 50 pounds), you will have applied force and exerted energy, but no work will have been done.

I see no reference to what is exerting the force, hence it is out sive the control volume and no energy will have been fed into the control volume.

Posted
Go on then.......

A rich oil sheik  has a stable of race horses and wants to make them into winners so he hires a chemist a physicist and a biologist to see what they can do. The three return 3 months later and the biologist says: "I know how to make faster horses but it will take me at least 6 generations of breeding." The Sheik considers for a few moments and says: "No, that will take too long. What have you got, chemist?"

Chemists says: "I have made some substances in my lab, but they are illegal." Again the sheik says no. The physicist steps forward and says I have done the calculations and I have found a way of making your horse 5 times faster than all others, unfortunately it only works for a spherical horse in vacuum!

If you're not rolling on the floor laughing now you are not a physicist!

Posted

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