Mass

Mass is defined as the amount of matter in an object.
Mass is different from weight, which is defined as a measure of the force of gravity acting on an object.

A scale is a device to measure mass.
There are two types of scales:

Mass is measured according to the same systems used for measuring length. The standard U.S. Customary Unit for measuring mass is the pound. The standard unit of the Metric System is the kilogram. The table below shows these two systems of measurement.


When to Use Which Unit?


When measuring the mass of a very small object, such as a leave, the best unit to use is the milligram.

The mass of a slighlty larger object, such as an apple, is measured using grams.

Large objects, such as a person, can be measured using kilograms or pounds.

When measuring even LARGER objects, like an elephant, the best units to use are tons or kilograms.


Table of Mass Conversions

U.S. Customary Units
16 ounces 1 pound
14 pounds 1 stone
2,000 pounds 1 tons

Metric System
1,000 milligrams 1 gram
1,000 grams 1 kilogram
1,000 kilograms 1 tonne


How Much Heavier is Your Brain after learning all this new information about mass?
Find out by visiting the mass exercises page!


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