A car is traveling at a constant speed of 27.1 m/s on a highway. At the instant this car passes an entrance ramp, a second car enters the highway from the ramp. The second car starts from rest and has a constant acceleration. What acceleration must it maintain, so that the two cars meet for the first time at the next exit, which is 2.81 km away?

1 answer

To travel 2.81 km, and reach the next exit at the same time, the time spent getting there must be
t = 2810/27.1 = 103.7 s.
Require that
(1/2) a t^2 = 27.1 t, and
solve for a, using the t from above.

a = 54.2/t = 0.523 m/s^2