Understanding Torque

[jon@harrison.ne]

As a PhD in Mechanical Engineering I can't resist commenting on this statement by Old Dog, who otherwise made a lot of correct statements. HP is simply one commonly used unit of power and has nothing to do with whether it is produced in linear or rotational motion. For example, a solid rocket engine has no rotational parts, in fact it has no moving parts of any kind, but it sure can have a lot of power, which we can express in HP, watts, Btu/min.,....

[olddog]

Originally Posted by jon@harrison.ne

As a PhD in Mechanical Engineering I can't resist commenting on this statement by Old Dog, who otherwise made a lot of correct statements. HP is simply one commonly used unit of power and has nothing to do with whether it is produced in linear or rotational motion. For example, a solid rocket engine has no rotational parts, in fact it has no moving parts of any kind, but it sure can have a lot of power, which we can express in HP, watts, Btu/min.,....

True. 1 Hp is also defined to be 745-ish watts. So indeed, you can measure your electric bill in Hp if you wanted to. And, you could convert the Btu rating of your furnace to Hp, as well. Yes in a true technical definition Power is Power, however in the real world Hp is used to rate engines and motors.

So saying Hp is associated with rotation, although it is not technically correct, in reality it is about the only time that unit of measure is ever used in the real world. For my intended purpose I might argue close enough, however I started down this road complaining about someone else miss stating and confusing the issue, so I stand corrected.

I'm a bit disappointed that you just tossed that out and moved on without adding much to the subject at hand, as I suspect you could easily do so, much more eloquently than myself.