Weight to Mass

[Lt Cmdr Matt]

FOr realism if you want to use mass instead of weight divide the weight by 2.2

198 Pounds / 2.2

Just a little tidbit I thought I would pass on.

[Greg Smith]

Isn't that just the conversion from pounds to kilos?

[Lt Cmdr Matt]

Exactly, Kilograms is the measure of Mass. A measure of weight is in either Pounds or Newtons. Newtons can only be used on Earth because the pull of gravity on a 1 KG object is 9.8 N. This is solely dependant on the equation W=mg. M stands for Mass which is Kilograms and little g for the Earth's pull on us which is 9.8. You could also use the equation F=G(mm/r^2)

Big G is the gravitational constant of 6.673x10^-11 times the masses of the two objects divided by the radius^2. It will give you the same number.

[Sea Tyger]

Actually, that's wrong. Pounds (lb) are used for both mass (lbm) and weight (lbw) in the Imperial system. They are simply considered equivalent in Earth-normal gravity.

So, someone who weighs 180lb. on earth has a mass of 180lbm.

Tyger Einstein

[Lt Cmdr Matt]

Wait ST, the unit of Mass in the imperial system is the slug. Pounds are still weight.

TO be more correct Kilograms is mass, Newtons and Pounds are a unit of force most commonly.

[Sea Tyger]

Originally posted by Lt Cmdr Matt
Wait ST, the unit of Mass in the imperial system is the slug. Pounds are still weight.

Then I guess my physics professors are all wrong. I was taught pounds-mass was the unit of mass in the imperial system..and considering the prestige of the school I attended those classes, I'll take their words over yours.

[Lt Cmdr Matt]

I respect that. I never said that there is no way that I was wrong. I very well could be. I would trust your professors over me at anytime for now. I respect that fact that you didn't flame me though.

[Lt Cmdr Matt]

In the English and Metric systems, Pounds are a measure of force not mass. Kilograms is a measurement of Mass. I researched the imperial system and I read about the Pounds are not mass but that is not in question. What I originally meant was that if you go to the moon your weight will be less your mass will be the same. That was what I was trying to say and that to be realistic in sci-fi you should use Kilograms, to do that from pounds in America you divide by 2.2.

I simply gave the equation of finding the force in newtons that can be used universally. Newtons are a force.

[Cmdr Powers]

I also was taught that the imperial measure of mass was the slug. It takes 32.2 pounds at sea level on Terra to make 1 slug.

OTOH, I'd really rather use metric!