How to find the displacement with such little info?

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The discussion revolves around calculating the average velocity of a glider moving with constant acceleration on an air track, using data from two flags that interrupt a photogate timer. The flags are 25.4 mm long, and the distance between their midpoints is 162 mm. Users express confusion about what value to use for displacement in the calculations. The average velocities at the moments the flags interrupt the timer are sought, but the exact displacement needed for calculations is unclear. Ultimately, one participant indicates they have resolved their confusion.
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A glider on an air track moves in the +X direction with a constant acceleration.? It has two flags, each exact?
A glider on an air track moves in the +X direction with a constant acceleration.?
It has two flags, each exactly 25.4 mm long, with the midpoints of the flags separated by 162 mm. The first flag interrupts the photogate timer for a time 50 ms, and the second flag interrupts the photogate timer for a time 45 ms.

1) What was the average velocity of the glider when the first flag was interrupted?

2) What was the average velocity of the glider when the second flag was interrupted?

I don't get it.. What do I plug in for the displacement? Is the 25.4mm or 162mm?


How do I find the displacement with such little information?
 
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Nevermind! I think I figured it out.
 
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