Unit Conversions

Chapter 2: Measurement and Problem Solving
 Convert between units.
 Convert units raised to a power.
 How many seconds are in 532 days?
 Units are multiplied, divided, and
canceled like any other algebraic
 Using units as a guide to solving
problems is called dimensional
 Always write every number with its
associated unit.
 Do not let units appear or disappear
in calculations. Units must flow
logically from beginning to end.
Conversion factors
are ratios
constructed from
any two quantities
known to be
Conversion factors can be inverted because
they are equal to 1 and the inverse of 1 is 1.
 In solving problems, always check if
the final units are correct, and
consider whether or not the
magnitude of the answer makes
When converting quantities with units
raised to a power, the conversion factor
must also be raised to that power.
Convert 7.8 km to miles.
Convert 0.825 m to
One lap of a running track
measures 255 m. To run 10.0
km, how many laps should
you run?
A circle has an area of
2659 cm2. What is its area
in square meters?
An automobile engine has a
displacement (a measure of the
size of the engine) of 289.7 in.3
What is its displacement in cubic