Question

Two runners star at the same time and run in the same direction. Runner A runs at a constant speed of 5 m/s; runner B at a constant acceleration of 0.2 m/s2 (starting with no initial speed). How long does it take to runner B to reach and pass runner A?

Answer 1

The solution would be much easier from the frame of reference of either runner.

Answer 2

I would use the formula x = (vo)t + .5at^2 for each runner. Notice that at the distances will be equal at the passing time. Let me know what you get if that helps. :)