[Help] Trains A and B are traveling in the same direction on parallel tracks. Updates to this post /post/159815-trains-a-and-b-are-traveling-in-the Sun, 07 Sep 2008 20:15:15 +0100 Reply from Plox Nork /post/159815-trains-a-and-b-are-traveling-in-the#reply-3726188 Oops my suggestion was wrong. -_-

]]> Plox Nork Sun, 11 May 2008 20:00:14 +0100 Reply from Anonymous /post/159815-trains-a-and-b-are-traveling-in-the#reply-3726097 It’s pretty straight forward if you think of it this way…

Train A starts off at the station (assume it instantly hits 80 mph) at 5:10.
Train B starts off at the same station (assume it instantly accelerates to 90 mpg) at 5:22. If you think of it this way, you realize it’s not starting position is not important.

distance traveled is assigned a variable “D”.

Since train B starts off 12 minutes later than train A, train A has 12 more minutes to travel.

so the question is, when does D for train A equal D for train B.
also important. when B catches up to A, train A has been traveling at 80 MPH for T minutes where B has been traveling for T-12 minutes (12 minutes less)

so…

80*T = 90 *(T-12)

8/9 = (T - 12) / T

8/9 = 1 - 12 / T

12/T = 1/9

T/12 = 9/1

T = 12 * 9

T = 108 minutes. Both trains will have traveled 144 miles by the

]]> Anonymous Sun, 11 May 2008 19:26:09 +0100 Reply from Plox Nork /post/159815-trains-a-and-b-are-traveling-in-the#reply-3726095 First you need to find out how far apart the two trains are. When you have that distance you can take the difference in speed as the speed at which they are closing in on each other. When you know these two things you can easily calculate when B will catch up to A.

]]> Plox Nork Sun, 11 May 2008 19:25:47 +0100 Reply from sarahjuanita198 /post/159815-trains-a-and-b-are-traveling-in-the#reply-3726091 Well if you’re looking for a speed distance and time equation, you always need to know speed = distance diveded by time, distance = speed multiplied by time and time = distance diveded by speed. If you follow this rule. Unless the faster train stops then the slower one will never catch it up…

]]> sarahjuanita198 Sun, 11 May 2008 19:24:57 +0100