Understanding Position-Time Graphs: Can They Determine Speed?

[noodles]

Can the position-time graph tell you the speed?
I thought it was ONLY velocity.

Can you please give me an example when IT DOESN'T allow you to find the speed?

Thanks so much in advance!

 

[Orodruin]

Speed is the magnitude of the velocity, if you can find the velocity you can always obtain the speed.

 

[CWatters]

Presumably we are talking about motion in one dimension, otherwise it's not clear what the position axis represents.

In which case a graph of position vs time gives you speed and velocity. The direction component of velocity comes from the slope of the line. +ve slope is away from the origin, -ve slope is towards the origin.

 

[brainpushups]

Just to piggyback for additional clarity: if you find the slope of the tangent line on a position vs. time graph you have found the velocity at that instant. The absolute value of the slope is the speed.