Analyzing motion diagrams (easy)

[samxel]

Homework Statement

If i have a picture of a motion diagram of 2 objects , how do i tell when they have the same speed and acceleration?
and at what time one object is ahead of Object B ?

I have a diagram here
http://i33.tinypic.com/28kpk02.jpg

Homework Equations

none

The Attempt at a Solution

Since they are both moving in the same direction I see the B is moving in constant speed
(same amount of displacement in each equal intervals of time)
So they may have the same speed at t=1 and t=4 OR they may have the same speed in between t=1 and t=4 ? Just can't figure Which.

 

[kuruman]

Try again. At t=1 and t=4 they have the same position not the same velocity. Look for equal displacements (differences in position) over the same time interval.

 

[tomcue]

To determine if the objects have the same speed, you can look at the spacing between the arrows representing their positions. If the spacing is the same for both objects at any given time, then they have the same speed. In this case, it appears that the spacing is the same between t=1 and t=4, indicating that they have the same speed during that time interval.

To determine when one object is ahead of the other, you can look at the relative positions of the arrows at different times. For example, at t=2, Object A is ahead of Object B because its arrow is further to the right. At t=3, Object B is ahead of Object A because its arrow is further to the right. So, it appears that they switch positions between t=2 and t=3.