You have probably seen various kinds of car races on TV or at events such as the Grand Prix in Edmonton or in movies or games such as "The Fast and the Furious" or "The Need for Speed." An important element in these activities is the velocity at which the vehicles travel. Velocity describes the distance travelled during a specific time interval. You will learn more about velocity in this activity.

You can probably tell when you are going fast by several clues, such as feeling the wind in your face or seeing the countryside flash by. Scientists calculate velocity by looking at how far you go in a certain length of time. Velocity is measured in distance over time. For example, when you are travelling on most major highways in Alberta, the speed limit is 110 kilometres per hour. If you are travelling in a school zone, the speed limit is 30 kilometres per hour. If you were measuring the speed at which a glacier melts, you might describe it in a measurement of metres or centimetres per year. (If it were kilometres per hour, look out for the flood!)

You might think velocity is the same thing as speed, and you are basically right. However, scientists use velocity to describe the direction an object is moving in addition to how fast it is moving.

 That is important when you are thinking about safety in road transportation and calculating the speed of vehicles going different directions. When you consider velocity, you can take the different directions of different vehicles into consideration. 

Because you know that velocity is measured in terms of distance covered over a particular period of time, the equation used to calculate velocity may seem obvious. It is:

NOTE: Velocity is always measured in metres per second (m/s).