Wed January 26, 2011 By:

can dimensional analysis be used to convert one system of unit to another system?

Expert Reply
Wed January 26, 2011
Dear student,
Dimensional analysis is a process where conversion factors are used to cancel units so
that one unit is converted into another.  The basic idea behind dimensional analysis is as follows:
 Identify the unit(s) that is(are) given. This will be a clue as to how you will
proceed with the rest of the problem.
 Identify the unit that is requested. This is what you are asked to solve.
 Identify any conversion factors that you may need. These may include
English‐to‐English, English‐to‐metric, or equivalence conversion factors such
as speed or density.
 Arrange the conversion factors such that the unit in the conversion factor
cancels out the unit you have. Continue in this manner until you have the
desired units.
Suppose we wish to know how many inches are in 22.4
km. Lets look at this problem with the above steps in mind.
 Identify the unit that is given.
In this problem the given unit is “km.” We are given 22.4 km.
 Identify the unit that is requested.
In this problem we are asked to find this distance in inches. “Inches” is the
unit we need.
 Identify any conversion factors.
We will need the following conversion factors:
1 km = 103 m 1 cm = 10‐2 m 1 in = 2.54 cm
 Arrange the conversion factors such that units cancel.
Hope this helps.
Thanking you
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