Active Learning – Chap 2 - 1D Kinematics and Free Fall 36. (II) An inattentive driver is traveling 18.0 m / s when he notices a red light ahead. His car is capable of decelerating at a rate of 3.65 m/s2 . If it takes him 0.200 s to get the brakes on and he is 20.0 m from the intersection when he sees the light, will he be able to stop in time? Active Learning – Chap 2 - 1D Kinematics and Free Fall 55. (II) A helicopter is ascending vertically with a speed of 5.10 m / s. At a height of 105 m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground? [Hint: for the package equals the speed of the helicopter.] Active Learning – Chap 2 - 1D Kinematics and Free Fall 29.The position of an object is given by x = At + Bt 2 , where x is in meters and t is in seconds. (a) What are the units of A and B? (b) What is the acceleration as a function of time? (c) What are the velocity and acceleration at t = 5.0 s ? (d) What is the velocity as a function of time if x = At n + Bt m ? What about if x = At n Bt m ?