Car acceleration calculation problem

AI Thread Summary
A train is moving at a constant speed of 33 m/s while a car, initially 32 m behind, travels at 47 m/s and accelerates at 4 m/s². To find the car's speed as it passes the train, the distance equations for both the car and the train must be equated. The car's distance can be expressed using the formula for uniformly accelerated motion, while the train's distance is based on its constant speed. By setting the two distance equations equal, the time at which the car passes the train can be determined, allowing for the calculation of the car's speed at that moment. Understanding how to set up and solve these equations is crucial for finding the solution.
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Homework Statement


A train is moving parallel and adjacent to a highway with a constant speed of 33 m/s. Initially a car is 32 m behind the train, traveling in the same direction as the train at 47 m/s and accelerating at 4 m/s^2.
What is the speed of the car just as it passes the train? Answer in units of m/s.



Homework Equations


So far, I have thought of using delta x= Vot+ 1/2at^2
I also think that I have to account for the displacement between the two trains, which is 14 m.
The thing that I don't understand is how to calculate something as it passes or catches up to another thing.

If there is any advice, thanks!
 
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Let the point when the measurement starts be s=0, then you have all the initial conditions. Now consider the distance s as a function of time t, so s(0)=0 for the car and s(0)=32 for the train. Write two such formulae, one to describe each object. At the point where the car passes the train, the two distances are the same, so you can equate and get a time value t_{m}, where then you can calculate the speed of the car with the formulae describing uniform acceleration.
 
bel said:
Let the point when the measurement starts be s=0, then you have all the initial conditions. Now consider the distance s as a function of time t, so s(0)=0 for the car and s(0)=32 for the train. Write two such formulae, one to describe each object. At the point where the car passes the train, the two distances are the same, so you can equate and get a time value t_{m}, where then you can calculate the speed of the car with the formulae describing uniform acceleration.

Yes, but I don't understand how to go about doing that. Like getting the two distances to equal the same? I did think of that as well, but didn't know how to use formulas to do something like that.
 
Say, for the train, which is initially (i.e., at time t=0) 32 metres ahead of the car, and travels with a constant velocity, say v_{train}. Then we have for the train s=32+v_{train}t.
 
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