Hi, can somebody explain how to get to the answers? a) 112 s, b) 4480 m.
I tried 2 methods but got different results each time. Thanks!
Sorry to bother with this topic again, but there is something unclear to me still. We already added +50 seconds in the beginning when we defined s1. Why do we need to add 50s again, wouldn’t that make it a total of 100s instead of 50? Let me know if my question is clear enough
Understood. Thanks for your question.
The time “t” you find through solving the problem, is the real/actual time train B uses when it travels without delay and this time belongs only to train B.
Considering the 50 seconds delay in our calculation, you can think it as “no motion for train B” in these 50 seconds. So, Train B does not use any time for any movement. But … Train A uses these 50 seconds for its movement/displacement. So, the time train A uses will be the time train B uses which is “t” plus 50 seconds more - while train B stands still but train A keeps moving. It results in a total used time of travel t+50 for train A.
Write me back if it is still unclear or questionable.
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