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    Hey guys,

    I don't know whether this is the right place to come but I need some help with a physics question, please take note that this isn't very high end stuff so you need not to worry lol. ( I know it's probably very easy but I'm in need of reassurance from people if I am to answer it.)

    So the question is as follows:

    A car moving at 20m/s has 160 000J of kinetic energy. Write down an equasion and then use it to calculate the average braking force acting on the car to bring it to rest over a distance of 25m.

    Now I'm assuming that the equasion would be something to do with force but that's the reason I'm here, I'm not quite sure how to answer it.

    So if somebody knows how to answer this question I would highly appriciate it if you could take me along steps of how about going to answer this question.

    Thank you for reading and I hope that someone knows how to figure this one out!
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    Work done = force*distance

    The work done in this case has to equal the kinetic energy of the car. In order for the car to be at rest, its kinetic energy must be equal to zero.
    The distance 25m is given to you in the question.
    The equation above can be rearranged to find the required force:

    work done/distance = force.

    Put the values into the above formula to find the average force needed to bring the car to rest in 25m. Remember the units of force are N (newtons).
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    Thank you very much
 
 
 
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