Minimum distance to avoid a collision

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To determine the minimum distance required to stop a car before colliding with a wall, the initial velocity of the car (19.0 m/s), its mass (1500 kg), and the maximum horizontal force exerted by the pavement (6000 N) must be considered. Applying Newton's second law (F=ma), the acceleration can be calculated as the force divided by the mass, resulting in a constant deceleration. The distance to stop can then be found using kinematic equations, specifically relating initial velocity, final velocity, acceleration, and distance. The assumption that the force of 6000 N is the frictional force acting on the car after braking is valid, as it dictates the car's deceleration. Understanding that the acceleration is constant allows for the correct application of the formulas needed to find the stopping distance.
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Homework Statement


While learning to drive, you are in a 1500 kg car moving at 19.0 m/s across a large, vacant, level parking lot. Suddenly you realize you are heading straight toward a brick sidewall of a large supermarket and are in danger of running into it. The pavement can exert a maximum horizontal force of 6000 N on the car.

The Attempt at a Solution


Suppose you apply the brakes and do not turn the steering wheel. Find the minimum distance you must be from the wall to avoid a collision

could somebody give me some hints on this? i can't figure out any method to find the minimum distance the car will stop before hit the wall.
since the question never say it is under a constant acceleration or increasing deceleration, how do i know what formula should i use?
i try to use F=ma, but it seems like lack of some information.
 
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You know your initial velocity and your final velocity. You can find out your acceleration since you know your mass. Now you just need to find the distance that acceleration would have to be applied in order to change between your initial and final velocities.
 
BAnders1 said:
You know your initial velocity and your final velocity. You can find out your acceleration since you know your mass. Now you just need to find the distance that acceleration would have to be applied in order to change between your initial and final velocities.

but how do i know the acceleration is constant or not?

and why i could assume the force before collision is 6000N since it is the force exerted for collision?
 
The question mentions that the pavement is providing the force, so I'm assuming it means the force of friction on the car after brakes are applied.

For the acceleration, you know that the car's mass is a constant, as well as the force on the car. If F=ma, then the acceleration must also be constant.
 
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