The Police Car and the Speeder - Part 1 - On screen capture


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A police Officer is at rest, when a speeder goes by. The Police Officer checks to make sure his lane is clear (that's why there is a delay before he accelerates!) and starts to accelerate to catch the speeder. (Consider the "measuring points" for the cars to be the back end of the cars .. thus the Police Car is at X=0 in this picture.)        Display Options :    X coordinate not shown         X coordinate shown         Vx coordinate shown         Ax coordinate shown


A) How fast is the speeder going?
B) How long does the Police Officer wait until he starts moving? (Assume he starts his stopwatch when the backs of the cars line up.)
C) How many seconds (from when the Police Car starts) will elapse before the Police Car catches the Speeder?
D) What is the acceleration of the Police Car (assuming it is constant)?


A) Vtruck = 3 m/sec.
B) The Police Officer pauses for 2 seconds before accelerating.
C) The Police Officer will catch the Speeder in just less than 3.7 seconds. [corrected 9/17/01]
D) The Police Officer has a constant acceleration of 4 m/sec2. [corrected 9/17/01]

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