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Speed and Velocity
SPEED is the distance something travels in a certain amount of time:
In SI units, distance is measured in METERS (m), time is measured in SECONDS (s), and speed is therefore measured in METERS PER SECOND (m/s).
When something is in motion, it doesn't necessarily stay at the same speed the entire time - it can change speeds and move faster or slower between its stopping and starting points. If that is not the case, we use AVERAGE SPEED, or the total distance something has traveled divided by the total time it has traveled. INSTANTANEOUS SPEED is the speed at a certain given moment. For instance, an Olympic sprinter who runs the 100-meter dash in 10 seconds might seem like she would be going 10 m/s, but that's just her AVERAGE speed. Near the finish line she's probably going much faster.
When something is in motion, it doesn't necessarily stay at the same speed the entire time - it can change speeds and move faster or slower between its stopping and starting points. If that is not the case, we use AVERAGE SPEED, or the total distance something has traveled divided by the total time it has traveled. INSTANTANEOUS SPEED is the speed at a certain given moment. For instance, an Olympic sprinter who runs the 100-meter dash in 10 seconds might seem like she would be going 10 m/s, but that's just her AVERAGE speed. Near the finish line she's probably going much faster.