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10 Nov 2019

A train has a length of 112 m and starts from rest with a constantacceleration at time t = 0 s. At this instant, a car just reachesthe end of the train. The car is moving with a constant velocity.At a time t = 21 s, the car just reaches the front of the train.Ultimately, however, the train pulls ahead of the car, and at timet = 42 s, the car is again at the rear of the train. Find themagnitudes of the following quantities.
(a) the car's velocity
m/s

(b) the train's acceleration
m/s2

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Trinidad Tremblay
Trinidad TremblayLv2
19 Apr 2019

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Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

Related questions

A train as a length of 92 meters and starts from rest with aconstant acceleration at time t=0seconds. At this instant, a carjust reaches the end of the train. The car is moving with aconstant velocity. At a time t=14 seconds, the car just reaches thefront of the train. Ultimately, however, the train pulls ahead ofthe car, and at time t=28 seconds, the car is again at the rear ofthe train. Find the magnitudes of a). the cars velocity and b). thetrain's acceleration.
I do not know how to set up the problem. Please explain why eachstep was done that way.

vf = vi + at
rx = vit + ½ at2
vf2 = vi2 +2arx
rx = ½ (vi + vf)t

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I no this is alot of questions but im having trouble answeringthese! So please help me..

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