Question

. A jeep is traveling on a straight road and it leaves a junction at time t = 0 second. It is then accelerates at 4 m/s 2 for 4 seconds. Suddenly, when the driver shifting the gears, there is no acceleration of the jeep for 1 second. After that, it is continue to accelerates at 5.5 m/s 2 for 5 seconds and maintain the speed it reached. On the other hand, a car leaves at the same junction as jeep at time t = 0 second. The car accelerates from rest to 25 m/s in 20 seconds and then maintain the speed of 25 m/s. The car passes the jeep as they both pass a traffic light. (i) Sketch speed vs. time graph to illustrate the motion of the jeep and the car by using same diagram. (ii) Find the distance of the traffic light from the junction. (iii) After 4 seconds from the constant speed, both jeep and car decelerates to rest in T seconds. Determine the value of T. (iv) If the car in this motion has zero speed at some instant in time, is the acceleration necessarily to be zero at the same instant? Prove your answer with some calculation example. (3

Answer 1