- #1

opus

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## Homework Statement

Two trains, each having a speed of 30km/h, are headed at each other on the same straight track. A bird that can fly 60 km/h flies off the front of one train when they are 60 km apart and heads directly for the other train. On reaching the other train, the bird flies directly back to the first train, and so forth. What is the total distance the bird travels before the trains collide?

## Homework Equations

All constant acceleration equations:

##v = v_0 +at##

##x-x_0 = v_0t + \frac{1}{2}at^2##

##v^2 = v_0^2 + 2a(x-x_0)##

##x-x_0 = vt - \frac{1}{2}at^2##

##x-x_0 = \frac{1}{2}(v_0+v)t##

## The Attempt at a Solution

Haven't made any progress. There seem to be a lot of moving parts so I just started off trying to find when the trains collide which would be when their x position is equal. I can't seem to pin down what values I can use in what equations to get this. Any hints? I've attached an image to show my drawing.