How Do You Calculate When One Moving Object Overtakes Another?

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To determine when the automobile overtakes the truck, the equations of motion for both vehicles must be analyzed. The automobile accelerates from rest with a constant acceleration of 2.0 m/s², while the truck travels at a constant speed of 9.3 m/s, starting 13.4 m ahead. The position of the automobile can be expressed as x(t) = 0.5 * a * t², and the truck's position as x(t) = x₀ + vt, where x₀ is the initial position and v is the speed. By equating the two position equations, the time and distance at which the automobile overtakes the truck can be calculated. Understanding these kinematic equations is crucial for solving the problem accurately.
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kinematics question help please :)?

So I've tried to attempt this problem by finding possible things like time or velocity but it just does not come out right. Help is greatly appreciated :)

Problem:

At the instant the traffic light turns green, an automobile starts with a constant acceleration a of 2.0 m/s^2. At the same instant a truck is 13.4 m down the road and traveling with a constant speed of 9.3 m/s. (a) How far beyond the traffic signal will the automobile overtake the truck? (b) How fast will the automobile be traveling at that instant?

heres some work I did:
Truck:
v=x/t
9.3=13.4/t
t= 1.44 sThanks :)
 
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If you know how far are the truck and the car from the traffic light at any moment, this problem is easy to solve.

So, for the car you have

x(t)=\frac{1}{2}at^2.

And for the truck

x(t)=x_0+vt.

Now you just need to figure what is x_0 and what is the condition for the car and the truck to meet.
 


What is x(t)?
 


kittykatxox said:
What is x(t)?

x(t) is the function with t as a variable. It tells you what is the distance x from the traffic light at the time t.
 
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