SOLUTION: train at the speed of 72 km/h, turned off the engine and 2 minutes later the train came to a stop. how big was the train acceleration and how long distance did it take to stop?

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Question 1024770: train at the speed of 72 km/h, turned off the engine and 2 minutes later the train came to a stop. how big was the train acceleration and how long distance did it take to stop?
sorry if somethings wrong i tried my best to translate the words from my language to english
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Convert all units to seconds.
t=2%2860%29=120s
v%5Bi%5D=72%281%2F3600%29=1%2F50km%2Fs
.
.
.
a=%28v%5Bf%5D-v%5Bi%5D%29%2Ft
a=%280-1%2F50%29%2F120
a=-1%2F6000km%2Fs
.
.
.
v%5Bf%5D%5E2=v%5Bi%5D%5E2%2B2ad
d=%28v%5Bf%5D%5E2-v%5Bi%5D%5E2%29%2F%282a%29
d=%280-%281%2F50%29%5E2%29%2F%28-2%2F6000%29
d=1.2 km