# Average speed between two points

if i have to find the average speed between two points, do i just subtract distance2 from distance1 and divide by the time interval? so it could be possible for the average speed to be 0 if whatever traveled equally length in both negative and positive direction?

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It is impossible for speed to be zero unless the body doesn't move at all. Average speed is the total distance over total time. If a person runs 5 km North and then 5 km South in a total of 1 hr, then the persons average speed is 10 km/hr. In this case, the average velocity is zero.

jtbell
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synx said:
if i have to find the average speed between two points, do i just subtract distance2 from distance1 and divide by the time interval?
To calculate average speed, use the total path length traveled by the object between the start and end points, as measured by something like a car's odometer, which follows the twists and turns of the path. To calculate average velocity use the straight-line distance between the start and end points of the path.

so it could be possible for the average speed to be 0 if whatever traveled equally length in both negative and positive direction?
No, this statement works only if you substitute "average velocity" for "average speed." The only way the average speed can be zero is if the object remains stationary, i.e. doesn't travel at all.

I understand now, thanks for clearing that up for me.