- #1
smsport
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Homework Statement
A train starts from rest. The train (including the locomotive and all the freight cars) is 120 m long. A person standing still next to the front train (not in front of it -- she is NOT run over!) notices that the end of the last freight car passes her exactly 2 minutes after the train started moving.
(i) What is the average speed of the train during the 2-minute time interval?
(ii) Assuming that the train accelerates at a constant rate, what is the speed of the train when the end of the last freight car passes the observer?
I can figure out i) just fine as average speed is 120m/120sec to get 1 m/s.
I don't know why ii) is confusing to me, but it is. It seems straightforward but I don't know how to get the speed of the train when it passes the person. Wouldn't it also be 1 m/s? Speed is just a scalar so how does acceleration come into play?