(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Two trains, each having a speed of 30 miles/hr, are headed at

each other on the same straight track. A bird that can fly 60 miles/hr flies

off one train when they are 60 miles apart and heads directly for the other

train. On reaching the other train it flies directly back to the first train

and so forth. (a) How many trips can the bird make form one train to the

other before they crash? (b) What is the total distance the bird travels?

2. Relevant equations

x=x_{i}+v_{x}t

3. The attempt at a solution

I know part b is 60 miles as the bird is flying at a constant 60mph until the trains crash, at one hour.

Part a is what is getting me, though I am thinking that it is technically an infinite number of trips as the bird always reaches the other train 2/3 of the way between the two, eventually making trips of minuscule distances. The whole reducing objects to a single point and all. Even if I started calculating the position of the trains after each trip the bird makes I would enter into limit territory, where the trains never collide, the just get closer and closer.

Am I just way over thinking this?

Thanks

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# Homework Help: Train Physics, One dimensional Motion

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