posted by Anonymous .
A "rocket car" is launched along a long straight track at t=0s. It moves with constant acceleration a1=3.0m/s^2. At t=2.5s, a second car is launched with constant acceleration a2=9.0m/s^2.
1. At what time does the second car catch up with the first one?
2. How far have the cars traveled when the second passes the first?
1/2 * 3t^2 = 1/2 * 9 (t-2.5)^2
t = 5.9
plug in that value for t into either expression.