Solve 1D Dynamics Problem: Can Car Stop Before Intersection?

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A car with a mass of 1100 kg is traveling at 60 km/hr and encounters a situation where the brakes fail 35 meters before an intersection. The coefficient of friction between the tires and the road is 0.45, which will affect the car's ability to stop. To determine if the car can stop before the intersection, the frictional force needs to be calculated to find the resulting acceleration. The relevant kinematic equations can be applied to analyze the motion, particularly focusing on the car's deceleration due to friction. The discussion emphasizes the importance of calculating the frictional force to solve the problem effectively.
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1D Dynamics Problem!

Homework Statement


A car of mass 1100kg is traveling at a constant velocity of 60 km/hr, east. The coefficient of friction between the tires and the road is 0.45.
The driver of the car sees the traffic light in front turning red and steps on the brake, only to find that the brakes are not working. If the car is 35m before the intersection when this happens, would it be able to come to a stop before entering the intersection?


Homework Equations


F = ma
d = vt + 1/2at^2
vf^2 = vi^2 + 2ad
vf = vi + at

The Attempt at a Solution



I've fiddled around with the bottom three kinematic equations, but I don't seem to be getting anywhere..
 
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hydra03 said:

Homework Statement


A car of mass 1100kg is traveling at a constant velocity of 60 km/hr, east. The coefficient of friction between the tires and the road is 0.45.
The driver of the car sees the traffic light in front turning red and steps on the brake, only to find that the brakes are not working. If the car is 35m before the intersection when this happens, would it be able to come to a stop before entering the intersection?


Homework Equations


F = ma
d = vt + 1/2at^2
vf^2 = vi^2 + 2ad
vf = vi + at

The Attempt at a Solution



I've fiddled around with the bottom three kinematic equations, but I don't seem to be getting anywhere..

It looks like you are supposed to assume the car is slowing down because of the 0.45 kinetic friction value. Start by trying to compute the acceleration a. To do that try to find the frictional force on the car first.
 
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