Speed is one of the most common forms of measurement. Just think about how many times you reference speed in a day. Just driving, how many times do you think about how fast you are going? Just like other measurements there are different systems of measurement for speed.
First, to understand speed, you need to understand how it is calculated. Speed is a rate measurement. It is the amount of distance travelled in a set amount of time. In the U.S. we often times look at speed in miles per hour. It’s fairly self-explanatory. If you are travelling at a speed that allows you to cover a distance of 5 miles in one hour, your speed is 5 miles per hour. If you travel 10 miles in 2 hours, your rate of speed is still 5 miles per hour.
Many times in navigation, you may hear of a speed term called Knots. This term is similar to our traditional miles per hour (MPH) speed rate. The difference is the length of the mile. In our traditional MPH rate, the mile is called a statute mile. A knot is another way of saying nautical mile per hour. A nautical mile length is slightly different that the statute mile length we normally associate with in the U.S. The reason that the two different mile measurements have been used is that the statute mile was evolved from surveying land, and nautical miles were evolved from seafaring navigation.
In addition to these forms of speed measurement, there is also the Metric system speed measurements. Luckily, there is a universal standard measurement for time, so length is the main concern when comparing speed measurements. Metric speed is found from using a metric form of length for the distance travelled per set amount of time. Some examples of metric system speed rates could be kilometers per hour, or even meters per second.
It is important to have a basic understanding of how speed is calculated, as well as how to convert between different standards. In addition to converting the length from US Standards to Metric Standards, it is also important to be cognizant of the time referenced in each speed rate. If a speed is measured in length per second, you should be able to convert that to it’s equivalent in length per hour.
For more practice on converting speeds and lengths, try some of the calculators below: