- 61

- 0

I am so close to figuring this problem out, but I just can't quite get it. Here's the problem:

At the instant the traffic light turns green, a

A) How far beyond its starting point does the car overtake the truck?

B) How fast is the car traveling when it overtakes the truck?

car: Vyi = 0, Ax = 2.8 m/s^2

truck: Vyi = 23.5 m/s, Vyf = 23.5 m/s, Ax = 0

1)If graphed, y-axis being distance and x-acis being time, the truck would like like a straight diagonal line, while the car would be sloping up, crossing over the truck's path at some point (I'll call it X). I am trying to find X.

2)I know I need to use two different kinematic equations and set them equal to each other, but this is where I start to not understand.

3) So, what I am trying to find is when the distance of both equations are equal to each other? So solve a couple kinematic equations for D then set them to each other right? Here's what I get:

(23.5 m/s)(T) = (1/2)(2.8 m/s^2)(T^2)

which turns out to be T = 16.79 seconds..is this correct? If it is I can use it to get the final answers for both A and B. Thanks guys!!

please don't waste your time with this, turns out I was right!

At the instant the traffic light turns green, a

*car*that has been waiting at an intersection**starts**ahead with a constant acceleration of**2.80 m/s^2**. At the same instant a*truck*, traveling with a**constant speed**of**23.5 m/s**, overtakes and passes the car.A) How far beyond its starting point does the car overtake the truck?

B) How fast is the car traveling when it overtakes the truck?

__Here is what is given:__car: Vyi = 0, Ax = 2.8 m/s^2

truck: Vyi = 23.5 m/s, Vyf = 23.5 m/s, Ax = 0

__here is what i know:__1)If graphed, y-axis being distance and x-acis being time, the truck would like like a straight diagonal line, while the car would be sloping up, crossing over the truck's path at some point (I'll call it X). I am trying to find X.

2)I know I need to use two different kinematic equations and set them equal to each other, but this is where I start to not understand.

3) So, what I am trying to find is when the distance of both equations are equal to each other? So solve a couple kinematic equations for D then set them to each other right? Here's what I get:

(23.5 m/s)(T) = (1/2)(2.8 m/s^2)(T^2)

which turns out to be T = 16.79 seconds..is this correct? If it is I can use it to get the final answers for both A and B. Thanks guys!!

please don't waste your time with this, turns out I was right!

Last edited: