Practice Test Questions: Truck Acceleration & 2-Block Friction System Analysis

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A truck accelerates from 20 m/s at 0.15 m/s², while a police car accelerates from rest at 0.6 m/s², starting 30 m behind. The discussion involves calculating the distance from the traffic light when the police catch the truck and plotting their positions over time. Additionally, there's an analysis of a two-block friction system to determine if it moves, along with calculations for tension and acceleration. Participants are encouraged to show their work and relevant formulas to facilitate problem-solving. The focus is on understanding the relationship between position, time, and acceleration in both scenarios.
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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
 
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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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