Matematika Ria
Tambahkan ke favorit Tambahkan ke favorit
link Tautkan di sini
Beranda Matematika RiaBeranda

Hak cipta © 2009

US Standard Mass (Weight)

These are the most common measurements:

  • Ounces
  • Pounds
  • Tons

Ounce weight!

"Ounce" is used for weight and for volume.

If you mean an ounce of weight, say "ounce weight",
but if you mean an ounce of fluid say "fluid ounce" ("fl oz")

Here we will talk about ounce weight



slice of bread

The smallest unit of weight is ounces (oz).  One ounce weighs about the same as a slice of bread.  It is very light.  

The abbreviation for ounce is "oz", because it came from the 15th century Italian word "onza".


When you add up the ounces you get a new label for weight.


If you have 16 ounces, it can also be called a pound (lb). 

1 pound = 16 ounces

The abbreviation is "lb", because it came from the Latin word "libra".

Typically, this is the unit that you use to measure your own weight. 

Pounds are used to measure lots of things from people to food to animals. 

However, if something weighs many pounds we use yet another label



Anything that weighs 2,000 pounds can also be weighed in tons.  One ton is the same as 2,000 pounds. 

1 ton = 2,000 pounds

That is really heavy!  Trucks, ships and heavy equipment are measured using tons instead of pounds.

An elephant weighs about 7 tons

And this car weighs about 2 tons.


But in some countries a "ton" can mean 2,240 pounds, so to be clearer people use "short" and "long" in front of "ton", like this:

  • A Short Ton is 2,000 pounds
  • A Long Ton is 2,240 pounds


Final thoughts about measuring weight:

1 pound = 16 ounces

1 Ton (also called "Short Ton") = 2,000 pounds = 32,000 ounces

1 Long Ton = 2,240 pounds

Weight or Mass?

We have been talking about weight here only because that is what people commonly say.

But we should really be calling these measures "Mass". See Weight or Mass? for a full explanation.

More About Ounces

"Ounce" normally means "Avoirdupois Ounce", but there is also "Troy Ounce"

  • The International avoirdupois ounce is 28.349523125 grams (normal meaning of "ounce")
  • The International troy ounce is 31.1034768 grams

More Examples

An ounce of mass is:

  • about 30 grams
  • exactly 28.349523125 grams

A pound is:

  • a bit less than half a kilogram
  • exactly 453.59237 grams (so a pound has a metric definition)

A short ton is:

  • about the weight of a small car
  • exactly 907.18474 kilograms