Lesson 13 — Activity 2:

Mass

 

Now that you have done some work on using imperial units to measure length, you will now turn your attention on how to measure the imperial units of mass. The most common units of measure when dealing with mass are the ounce, pound, and ton.


Ounce

An ounce is the smallest of the imperial units of mass that you will use. An ounce of mass is about 30 grams.

1 ounce = 28.349523125 grams

One ounce weighs about the same as a slice of bread. It is very light. Ounce is abbreviated as oz.

Image Source: Pixabay

Gold is measured in ounces.


Image Source: Pixabay

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

Pound

When we have 16 ounces, it can also be called a pound (lb). 

1 pound = 16 ounces

Pound is abbreviated as lb. Multiple pounds are abbreviated as lbs.

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


Ton

2,000 pounds is one ton. 

1 ton = 2,000 pounds

That is really heavy! Trucks, ships, and heavy equipment are measured using tons instead of pounds. A ton is abbreviated as t.

Image Source: Pixabay

An elephant has a mass of about 7 tons.


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

•A short ton is 2,000 pounds.
•A long ton is 2,240 pounds.

1 pound = 16 ounces

1 ton (also called "short ton") = 2,000 pounds = 32,000 ounces

1 long ton = 2,240 pounds


When working with imperial measurements of mass at school, at work, at home, or in your community, it is important that you choose the appropriate unit of measure. For example, if the doctor asked you how much you weigh, it would be better to tell him that you weigh 150 pounds instead of 2,400 ounces!


Let's practise choosing the appropriate imperial unit for mass.

For example, which is the best imperial unit of mass to use to measure a piece of bread?

  • ounces (oz)
  • pounds (lb)
  • short tons (t)

The most appropriate unit would be ounces (oz)!

Image Source: Pixabay


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What is the best imperial unit to use to measure a basket of fruit?

  • ounces (oz)
  • pounds (lb)
  • short tons (t)

The most appropriate unit would be pounds (lb).


What is the best imperial unit to use to measure a truck?

  • ounces (oz)
  • pounds (lb)
  • short tons (t)

The most appropriate unit would be tons (t)!

truck scale
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