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Homework Help: Practice test questions

  1. Oct 28, 2008 #1
    1.A truck passed a red light at a speed of 20 m/s and started accelerating at 0.15 m/s/s. A police car 30 m behind the truck started from rest with acceleration 0.6 m/s/s to pursuit the truck. Find the distance from the traffic light when the police caught up with the truck. Plot the position versus time information for the police car and truck on the same graph. Find the truck acceleration if the catch-up distance is double.

    2.Given the following 2-block friction system, does the system move? Show calculation
    If it moves, calculate the tension and the acceleration.
    a=2 kg, b=10 kg, u=.25, angle=30 degrees. find the acceleration and tension
    T-(2)(9.8) sin30 - (0.25)(2)(9.8) cos30 = 2a
  2. jcsd
  3. Oct 29, 2008 #2


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    Science Advisor
    Homework Helper

    Welcome to PF xxpundoxx.
    I assume you just missed the big bold letters that ask you to use the template and provide some work you have already tried, or at least write down some formulas you think might be relevant?

    Anyway, the question asks you to plot the position versus time graph of both the police car and the truck in the same graph. Before doing any calculation: how would this help you find the answer? Now give me a formula you are going to use to solve the question.
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