A car traveling 60 km/h accelerates at the rate of 2.0 m/s2. How much time is required for the car to reach a speed of 90 km/h?

Amoving freight car collides with an identical one that is at rest. if momentum is conserved, what happens to the second car after the collision? it attains the same speed as the first car. it moves at half the speed of the first car. it moves at twice the speed of the first car.