Calculating the Length of a Driveway Using the Work-Kinetic Energy Theorem

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To calculate the length of the driveway, the work-kinetic energy theorem is applied, where the net work done on the car equals its change in kinetic energy. The car's initial kinetic energy is zero since it starts from rest, and the final kinetic energy is determined using its mass and speed at the bottom of the driveway. The work done against friction is calculated using the friction force and the distance traveled, which is negative due to the opposing direction of friction. The equation Wnet = KE leads to solving for the length of the driveway. A complete solution requires showing all calculations to clarify the process.
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Homework Statement


A 2.1x103 kg car starts from rest at the top of a driveway that is cooped at an angle of 20.0° with the horizontal. An average friction force of 4.0 x 103 N impedes the car's motion so that the car's speed at the bottom of the driveway is 3.8 m/s. What is the length of the driveway.


Homework Equations


Wnet = KE

In other words: Work = m1v1/2 - m2v2/2

Work = force x distance


The Attempt at a Solution



Please give me some work along with the answer so I can understand how to complete the problem.
 
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Hi BadCo55! Welcome to PF! :wink:

Show us what you've tried and where you're stuck, and then we'll know how to help! :smile:
 
That's the thing, I really don't know how to start...
 
start with the work-energy theorem
 
Would it be d = -0.2625 ? Since it's frictional force I put -4.0x10^3
 
(just got up :zzz:)

please show your calculations :smile:​
 
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