When multiplying conversion factors, make sure the only remaining units are the desired units.
H
Practice makes perfect
We want to express 15 meters per second in kilometers per second.
15 m/s= km/s
This means that we need to change meters per second into kilometers per second. To do so, we will use the fact that 1 kilometer is equal to 1000 meters. Let's write this relationship as a unit ratio.
1000 m/1km
To perform the conversion, we need to multiply the speed in meters per second by the unit ratio or its reciprocal. Remember, we want to arrange these ratios such that every unit we do not want gets canceled out, and only the units that we want will remain.
We found that the the boat is traveling at an average speed of 0.015 kilometer per second. This means that the correct options is H.
Extra
Common Conversion Factors
Use the following tool to explore some of the most commonly used conversion factors. Conversions can be made both within or between the metric system and the imperial system, also known as the U.S. Customary System.
Around the world, people use conversion factors on a regular basis. You can read more about some practical applications of conversion factors in our original content.
