Factor – Label Method To convert units we need what we call a conversion factor. Conversion factors are valid relations between units of the same kind or equities expressed as a fraction. Steps to be followed for each conversion factor (fraction):1. Write down the quantity and the units you want to be converted. The symbol for the unit that we want to obtain will be placed in the place of the fraction where we want it to be (denominator or numerator). The symbol for the unit that we want to cancel (eliminate) will be placed in the remaining space of the fraction (numerator or denominator).2. In the conversion factor: Write 1 before the highest unit and the equivalent quantity before the other unit in the conversion factor..
Examples: 1. 1200 m to km 2. 72 km/h to m/s 3. 1,6 g/ml to kg/m3 Finalizar
1200 m to km 1 km 1200 · 11200 m x km 1,2 km 1000 m 1000 Unit we want to obtain Write 1 before the hightest unit (km are higher than m) Unit we want to eliminate goes in the denominator to cancel it . Here we will write the equivalent: 1 km equals1000 m End Other examples
72 km/h to m/s km 1000 m 1 h 72 · 1000 · 1 m m 72 x x 20 h 1 km 3600 s 1 · 3600 s sThis conversion This conversion factorfactor leaves m leaves permite s in the in numerator y denominator and allows us and km are to cance the h (numerator) cancelled (denominator) End More examples
1,6 g/ml to kg/m3 g 1 kg 1000000 cm3 1,6·1·1000000 kg kg 1,6 x x 1600 cm3 1000 g 1 m3 1000 · 1 m3 m3This conversion This conversion factor leaves permitefactor leaves kg m3 in the denominator and allows us in numerator y to cancel the cm3 (numerator) and g are cancelled (denominator) End More examples