Resource #7
Dimensional Analysis: Changing Between Units

image21.gif (1175 bytes) ----------> mpersec.gif (1015 bytes)

 Example
1. Rewrite the original problem in fraction form by putting the number over 1 and placing the units on the top and bottom of the fraction bar image23.gif (1190 bytes)
2. Circle the unit that is changing (cm) image23.gif (1190 bytes)
3. Put parentheses around the 1st fraction and setup a second fraction. image24.gif (1276 bytes)
4. In the 2nd fraction, put the unit that is circled on the opposite level it is located in the first fraction (top --> bottom) image25.gif (1289 bytes)
5. In the 2nd fraction, put the unit that the circled unit is turning into on the other level (top) image26.gif (1317 bytes)
6. In the 2nd fraction, put in the numbers in front of the units that make them equal (100 cm = 1m) image27.gif (1370 bytes)
7. Cross cancel the units and multiply across. image28.gif (1576 bytes)
8. Divide and write as a standard number, not a fraction, round to original number Significant Figures (4) image29.gif (977 bytes)