- Average speed can be calculated by dividing the total distance the object travels by the total amount of time it takes to travel that distance.
- While the speed of the object may vary during the total time it is moving, the average speed is the result of the total distance divided by the total time taken.
- Speed measurements contain a unit of distance divided by a unit of time. Examples of units of speed might include “meters per second” (m/s), “kilometers per hour” (km/h), or “miles per hour” (mph or mi/hr).
- Average speed can be calculated using the formula v=d/t where the variables are:
- v is the average speed of the object with units of m/s
- d is the total distance or length of the path of the object with units of m
- t is the total time taken to cover the path with units of s
- Speed cannot have a negative value.
Calculating Average Speed
(Speed and Direction)
- Velocity refers to both the speed of an object and the direction of its motion.
- A velocity value should have both speed units and direction units, such as m/sec north, km/h south, cm/s left, or km/min down.
- If an object is moving forward, it has positive velocity. When an object is moving backwards, it has negative velocity.
- When you throw a ball in the air, it has positive velocity. When it heads back towards you, it has negative velocity.
Speed vs. Velocity vs. Acceleration
- Investigate how acceleration is the rate of change in velocity.
- Solve problems for time or distance. Click here for some sample problems