Find the distance the car travels before it stops

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To determine the stopping distance of a car with a mass of 2000 kg traveling at 50 km/hr and a coefficient of friction of 0.3, the force of friction must be calculated as the product of the coefficient of friction and the normal force. The normal force equals the weight of the car, which is the mass multiplied by gravitational acceleration. The car's initial speed needs to be converted to meters per second. The work done by friction, which equals the force of friction times the stopping distance, should equal the change in kinetic energy of the car. Understanding these relationships allows for the calculation of the distance the car travels before it stops.
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A car wants to stop. The coefficient of friction is 0.3 and the mass of the car is 2000 kg. The car is traveling at 50 km/hr. Find the distance the car travels before it stops.

I know that the force of friction= the coefficient of friction x the normal force. I also know that I need to change 50 km/hr to m/s. I can't quite figure out how to find the normal force on this one(would i subtract friction from it or add it or what), and I don't see how I could find the distance it would take to stop because I do not know the time or the acceleration. Please help!
 
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The work of the frictional force must equal the change of kinetic energy of the car, start with that.
 
radou said:
The work of the frictional force must equal the change of kinetic energy of the car, start with that.

so does that mean that the force of friction equals the change in velocity?
 

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