A train starts from rest and accelerates uniformly at 0.60 m/s² [E] until it reaches a velocity of 24 m/s [E]. It travels at 24 m/s [E] for a certain amount of time, then accelerates uniformly at
-1.2 m/s² [E] until it comes to rest. The train's total displacement is 2400 m [E]. Find

a). the distance that the train travelled at
24 m/s [E].
b). the total time taken for the entire trip.

Question

A train starts from rest and accelerates uniformly at 0.60 m/s² [E] until it reaches a velocity of 24 m/s [E]. It travels at 24 m/s [E] for a certain amount of time, then accelerates uniformly at 
-1.2 m/s² [E] until it comes to rest. The train's total displacement is 2400 m [E]. Find

a). the distance that the train travelled at
     24 m/s [E].
b). the total time taken for the entire trip.

anonymous · Answer

take it easy.., the answer is:
a) the distance that the train travelled at 24 m/s is (s1) = 480 m
b) the total time taken for the entire trip is 200 sekon, or 1/18 jam..,

loot at the figure that i upload for you

calculusfunctions · Answer

Hi @gerryliyana thank you for trying!! I'm sorry to have to tell you that unfortunately your solution is incorrect. My students also had great difficulty with this problem although I think it's an excellent question to ask on a test. lol. I guess I wanted to prove to them that it is an easy question by posting it here and having other students solve it. I guess they were right considering that after eight days of posting, only one person out of many even attempted it. I commend you for that. I'm still hoping that others will try and that perhaps even you will redo the question again, with a different train of thought (pardon my pun). However if you choose to give up and wish to know the correct solution, let me know but I really hope you will persevere instead of quitting. I still haven't given up on my students either. Even though we have moved forward with a new unit, they're still encouraged to solve the problem. In fact some of them already have. Kudos to you and others who do not run from a challenge.

nubeer · Answer

ok first formula we need to remember..
a=v/t
v=24, a =0.6
so t =40s this is the time it took him to reach the velocity of 24m/s
lets suppose it moves with 24m/s for x secs.. and when the car start to decelrate at that point the time is "t"
now its better to draw the velocity time graph which will make this question alot easier.

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remember now t secs has been passed and its starting to declerate we can find the time it took to declerate..
v=24 , a =-1.2 as its decelrating we can take 1.2
so t = 20s ..

nubeer · Answer

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