[MHml] HP to Watts

[Paul Nudd]

I just wrote a long and detailled reply and accidentally deleted before sending.
Suffice to say that I am not sure about anything any more. When I was doing 1st year engineering physics in 1968 I was sure about lots of things but not any more.
The important thing is that an electric motor will produce it's max' torque either at 'stall' or when moving infinitesimily slowly and at this point it will be producing zero horsepower and yet lots of watts as the product of amps and volts.

My opinion is that internal combustion engines are best described and compared on the basis of their swept volume and number of cylinders e.g. 2litre 4 cylinder. I am not sure how best to describe and compare electric motors. And to compare a IC engine to an electric motor??? perhaps just max' sustainable torque??
PN
----------------------------------------
> Date: Sat, 15 Dec 2007 17:07:18 -0800
> From: rsirfj at shaw.ca
> To: multihulls at steamradio.com
> Subject: Re: [MHml] HP to Watts
> 
> 
> ----- Original Message ----- 
> From: "Paul Nudd" 
> To: "Informed discussion of multihull issues" 
> Sent: Saturday, December 15, 2007 4:02 PM
> Subject: Re: [MHml] HP to Watts
> 
> 
> producing huge amounts of torque - no, it can't because torque = force x 
> distance (radius) and force = mass x acceleration. No change in rpm means no 
> acceleration, thus no force, thus no torque.
> 
>         Are you sure about this Paul?  I had the impression that torque was 
> measured in pounds feet ( or metric equivalent) and pounds or kilograms are 
> masses which do not require acceleration in the usual sense to exert their 
> weight and that due to gravity does not require actual motion. It's a long 
> time since I was "into" definitions like that. How about Effort instead of 
> Force. Certainly that is what one applies to the end of a torque wrench 
> without moving the end of the handle hardly at all, moving it more slowly in 
> fact which is decelleration.  I guess there are terms of common use in the 
> none professional world which are clear enough in their everyday meaning 
> without precisely matching the scientific definition of the term. Perhaps 
> torque is one of them?
>>
>    Roy Mills 
> 
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