I would like to remind all users that, with respect to the unit of measurement corresponding to 1000.0kg, there are differences, depending on the country where you are, and that Mathcad takes this into account. so you have to be careful:
1 Tonne =1 metric tonne =1000kg
1 Ton = 1 imperial Ton (US) =2000 lb
what is missing is
1 Ton = 1 imperial ton (UK) =2240 lb
14 pounds = 1 stone; 8 stones = 1 hundredweight; 20 hundredweight = 1 ton)
Way back, when I was in school and introduced to the "metric system," the one major advantage that I saw over the "English" system was the complete separation of terminology between mass and force. Mass was grams, or kilograms; force was Dynes or Newtons. Things were clear, not like the English system where pounds could be force or mass. Equations were much simpler--devoid of the hated "g".
I was (and still am) very disheartened when I encounter a "kilogram force". I have been forced (by location) to learn and use the English unit system, and have gotten used to it. But please, please, please: Hold firmly to kilograms and Newtons, grams and Dynes. Practice the true religion; put "kgf" behind you!
You're absolutely right, but those units are used, especially in engineering, as you well know, when it comes to large masses or forces so write numbers relatively small, otherwise, for exmple, to write 10 tons (tonnef), you should write 98066,500N.