[1D kinematics] Car problem: Solving problem with a graph

AI Thread Summary
The discussion revolves around solving a kinematics problem involving a car's motion, which includes phases of acceleration, constant speed, and deceleration. Participants emphasize the importance of drawing a velocity versus time graph, which resembles a trapezoid, to visualize the car's journey. The conversation highlights the need to calculate areas under the graph to determine the time spent at constant speed. Suggestions include marking the constant speed level on the graph and using kinematic equations to relate the areas to the distances traveled. The overall focus is on applying graphical methods alongside traditional formulas to solve the problem effectively.
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Homework Statement


A car starts from rest and accelerates uniformly for 200m. It moves at constant speed for 160m and then decelerates to rest in 50m. The whole trip takes 33s. How long did it move at constant speed? (hint: draw the v versus t graph).


Homework Equations


kinematics equations
and the graph is used


The Attempt at a Solution


I drew the graph which looks like a trapezoid... but I don't know what to do after that.
 
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Delightful to see your teacher using the graphing method instead of just formulas all the time! Do you know how to put the distances on that graph? Got the constant speed level marked with a "v" or something? The method usually involves writing formulas for the areas. Once you have them written up you'll probably see how to finish it.
 

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