Calculating Frictional Work on a Moving Car

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To calculate the work done by friction in slowing a 1000 kg car from 29.8 m/s to rest, the kinetic energy approach is recommended. The kinetic energy equation, 1/2(m)v^2, is used to determine the energy converted to heat, which is essential for this calculation. The correct calculation yields 444,020 J of work done by friction. This method effectively captures the energy loss due to friction without needing the coefficient of friction. The approach and the final answer appear to be accurate.
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Homework Statement



How much work must be done by frictional forces in slowing a 1000kg car from 29.8m/s to rest?


The Attempt at a Solution



Im not quite sure how to go about this problem. I know the frictional force is 9800N times the coefficient of friction. And I know the car isn't accelerating prior to slowing down. I am not quite sure how to fit this all together. A little guidance would be greatly appreciated =)
 
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Working with the coefficient of friction is the wrong approach for this. Use an energy approach. How much energy must be converted to heat?
 
oh I get it I need to use the kinetic energy equation from 28.9 to 0?
 
I plugged it into the equation 1/2(m)v^2 and solved from 0 to 28.9. My answer was 444020 J. Does this seem like the right method?
 
Looks good!
 

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