Calculating Frictional Work for Slowing Down a Car

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To calculate the work done by frictional forces in slowing a 1000 kg car from 24.9 m/s to rest, one should focus on the car's mechanical energy before and after the motion. The initial kinetic energy can be determined using the formula KE = 0.5 * m * v^2. The work done by friction will equal the initial kinetic energy since it brings the car to a stop. It is important to set the frictional force equal to the force required to decelerate the car effectively. Understanding energy methods is crucial for solving this problem.
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Homework Statement



How much work must be done by frictional forces in slowing a 1000kg car from 24.9 n/s to rest

Homework Equations





The Attempt at a Solution



I just never fully understood how slowing down worked. I just need a nudge in the right direction not you guys doing the work for me. I don't think I'm supposed to do a force analysis, but then again I don't know how to do the problem.
 
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ecthelion4 said:

Homework Statement



How much work must be done by frictional forces in slowing a 1000kg car from 24.9 n/s to rest

Homework Equations





The Attempt at a Solution



I just never fully understood how slowing down worked. I just need a nudge in the right direction not you guys doing the work for me. I don't think I'm supposed to do a force analysis, but then again I don't know how to do the problem.
If you are familiar with energy methods, you should start there. Look at the car's mechanical energy at the beginning and at the end of its motion. Assume level ground.
 
You will set the frictional force equal to the force required to slow the car from 24.9 m/s to 0 m/s.
 
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