Find the constant acceleration of the train

AI Thread Summary
To find the constant acceleration of the train, the problem involves calculating the initial and final velocities based on the lengths of the train cars and the times they pass by. The initial velocity (vi) is determined by dividing the length of the car (8.60 m) by the time it takes for the first car to pass (1.50 s), while the final velocity (vf) is calculated using the time for the second car (1.10 s). The acceleration (a) can then be found using the formula a = 2(vf - vi)/2.6, where 2.6 seconds is the total time interval for both cars to pass. The discussion highlights the need for a kinematic equation that relates distance and time under constant acceleration. Understanding these calculations is essential for solving the problem accurately.
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Homework Statement


Liz rushes down onto a subway platform to find her train
already departing. She stops and watches the cars go by.
Each car is 8.60 m long. The first moves past her in 1.50 s
and the second in 1.10 s. Find the constant acceleration of
the train.


Homework Equations





The Attempt at a Solution


vi = 8.6/1.5
vf = 8.6/1.1
a = 2(vf - vi)/2.6
?
any advice? I'm confused
 
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You're given distance and time, so what kinematic formula relates those two for constant acceleration?
 

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