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What is the initial speed of the car assuming a level road?

Police lieutenants, examining the scene of an accident involving two cars, measure the skid marks of one of the cars, which nearly came to a stop before colliding, to be 79 m long.
The coefficient of kinetic friction between rubber and the pavement is about 0.70. Estimate the initial speed of that car assuming a level road.
m/s

Let initial speed 'u'=?.

As the car finally stops , final velocity 'v'= zero

distance s= 79 m

acceleration 'a =friction force /mass= -(mu) mg/m=(mu)g= -0.70*9.8= - 6.86 m/s^2

Assuming constant acceleration,

v^2 - u^2 =2as gives

u^2=v^2 - 2as

u = sq rt [v^2 - 2as] =sq rt [zero - 2as]=sq rt [ 2*6.86*79]= sq rt1033.8=32.922 m/s

Assuming a level road. the initial speed of that car is 32.922 m/s or 118.52 km/h