# Converting Units

Topics: Units of measurement, Metric system, International System of Units Pages: 3 (436 words) Published: May 28, 2013
Section 1.4—Converting Units
Often, a measurement is more convenient in one unit but is needed in another unit for calculations.

Dimensional Analysis is a method for converting between units.

Equivalents
Dimensional Analysis uses equivalents.

What is an equivalent?
Two measurements that have the same meaning. Ex:

What happens if you put one over the top of the other?

See your reference sheet for some common equivalencies.

We can use these conversion factors to switch between units! This “switching units stuff” is called Dimensional Analysis! The method I teach you today is important, I know there might be an easier way to you, but you need to trust me and go with it!

Dimensional Analysis
Dimensional analysis is based on using units to analyze how we solve a problem. We use the equivalents to show that two answers have the same meaning but they can be expressed in different ways. 27 inches –Can you figure out how many feet? Before we teach you Unit Analysis we must understand Canceling!

27 inches x __1 foot___
12 inches

Anything that is on the top and the bottom of an expression will cancel When canceling units…just cancel the units and NOT the numbers. (unless the numbers cancel out as well)

Steps for using Dimensional Analysis

1. Write down your given information.
2. Write down an answer blank and the desired unit on the right side of the problem space.
3. Write down a multiplication sign after your given information and then use an use an equivalent fraction to cancel the unwanted unit and get the desired unit. 4. Calculate the answer by multiplying across the top & dividing across the bottom of the expression.

Now let’s go to our 1.4 worksheet and practice a few…

Welcome back!

Metric Prefixes

Metric prefixes can be used in Dimensional analysis as well. I know you have learned these before! King...