An officer hiding at an intersection observes a car run a red light at constant
ID: 1629459 • Letter: A
Question
An officer hiding at an intersection observes a car run a red light at constant speed. The officer takes off in 2.0 after the car passes him. He accelerates at 6 m/s' for 8.0 seconds then maintains that speed until catches the car 1.0 minute later. a. How far are both from the intersection? b. How fast are both cars traveling? An object moving horizontally has the acceleration-vs-time graph shown. At t = 0, the object has x_0 = 0 and v_0 = 10m/s a. Draw a velocity-vs-time graph for the object. Include a numerical scale the vertical axis. b. Draw a motion diagram of the object's motion.Explanation / Answer
16. for officer,
until t = 2s , d1= 0
2s to 10sec, d2 = 0 + (6 x 8^2 / 2)= 192 m
10 sec to 70 sec, d3 = (6 x 8)(60) = 2880 m
total distance traveled = 3072 m
(A) Both cars are at 3073 m from intersection.
(B) Travelling time for Car = 70 sec
v = 3072 / 70 = 43.9 m/s