Will I Make the Crossing in Time?

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A driver traveling at 21 m/s is 44 m from a railroad crossing, while a train moving at 29 m/s is 56 m away. The driver realizes they cannot stop in time and must accelerate to cross before the train arrives. With a reaction time of 0.42 seconds, the driver needs to calculate the minimum acceleration required to safely cross the tracks. The discussion focuses on determining this acceleration to avoid a collision.
a.d.d92
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Very tricky question!

Help me try to figure out this problem please! :(

I was driving along at 21 m/s , trying to change a CD and not watching where I was going. When I looked up, I found myself 44 m from a railroad crossing. And wouldn't you know it, a train moving at 29 m/s was only 56 m from the crossing. In a split second, I realized that the train was going to beat me to the crossing and that I didn't have enough distance to stop. My only hope was to accelerate enough to cross the tracks before the train arrived. If my reaction time before starting to accelerate was 0.42 s , what minimum acceleration did my car need for me to be here today writing these words?
THANKS
 
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